WEBVTT 00:00:00.000 --> 00:00:02.060 Welcome to the Deep Dive, the place where we 00:00:02.060 --> 00:00:04.580 take the world's most complicated thinkers and 00:00:04.580 --> 00:00:07.719 systems, strip them down to their essential surprising 00:00:07.719 --> 00:00:11.099 components, and hand them to you ready to use. 00:00:11.300 --> 00:00:13.519 Today we are tackling a giant of intellectual 00:00:13.519 --> 00:00:17.329 history, Jean Piaget. This Swiss psychologist 00:00:17.329 --> 00:00:20.850 who lived from 1896 to 1980 fundamentally changed 00:00:20.850 --> 00:00:24.210 how we perceive not just children, but how all 00:00:24.210 --> 00:00:26.949 human beings learn and acquire knowledge. He's 00:00:26.949 --> 00:00:29.710 a huge figure. His shadow is so vast that he's 00:00:29.710 --> 00:00:31.670 routinely cited as the second most influential 00:00:31.670 --> 00:00:34.210 psychologist of the entire 20th century. Which 00:00:34.210 --> 00:00:35.890 is, I mean, that tells you everything you need 00:00:35.890 --> 00:00:37.630 to know about the impact here. Absolutely. So 00:00:37.630 --> 00:00:39.770 our mission today is a comprehensive deep dive 00:00:39.770 --> 00:00:42.229 into Piaget's world. We want to give you the 00:00:42.229 --> 00:00:44.490 shortcut to understanding his global theory of 00:00:44.490 --> 00:00:47.659 cognitive development. grasp his extremely technical 00:00:47.659 --> 00:00:50.359 -sounding concept of genetic epistemology, and 00:00:50.359 --> 00:00:53.179 trace his vast unexpected influence across education, 00:00:53.539 --> 00:00:55.979 philosophy, and even computer science. We've 00:00:55.979 --> 00:00:58.039 synthesized a collection of sources covering 00:00:58.039 --> 00:01:00.780 his entire life, the evolution of his complex 00:01:00.780 --> 00:01:04.859 theoretical models, and the significant influence 00:01:04.859 --> 00:01:08.439 and subsequent waves of rigorous scientific criticism 00:01:08.439 --> 00:01:12.120 that followed. By the end of this, you will understand 00:01:12.120 --> 00:01:14.939 the architecture of the developing mind as Piaget 00:01:14.939 --> 00:01:17.230 saw it. Okay, let's unpack this. When people 00:01:17.230 --> 00:01:19.790 hear Piaget, they immediately jump to the four 00:01:19.790 --> 00:01:22.409 stages, sensorimotor, preoperational, and so 00:01:22.409 --> 00:01:25.909 on. But to truly appreciate his genius, you really 00:01:25.909 --> 00:01:28.730 have to look at the man himself. His journey 00:01:28.730 --> 00:01:31.349 from a precocious teenager obsessed with aquatic 00:01:31.349 --> 00:01:34.310 life to a towering figure in developmental psychology 00:01:34.310 --> 00:01:37.209 is a story of constant intellectual reconstruction. 00:01:37.829 --> 00:01:39.909 What's so fascinating here is that he didn't 00:01:39.909 --> 00:01:42.790 even start as a psychologist. He was an epistemologist, 00:01:43.090 --> 00:01:45.180 a philosopher concerned with the very nature, 00:01:45.319 --> 00:01:48.140 origins, and scope of knowledge. Right, so he 00:01:48.140 --> 00:01:51.099 wasn't just asking how much kids know. No, not 00:01:51.099 --> 00:01:53.280 at all. He wasn't interested in testing children 00:01:53.280 --> 00:01:55.659 to see how much they knew, but rather how knowledge 00:01:55.659 --> 00:01:57.700 itself originates and qualitatively develops. 00:01:58.280 --> 00:02:00.540 This explains the name of his core theoretical 00:02:00.540 --> 00:02:03.780 project, genetic epistemology. Okay, so let's 00:02:03.780 --> 00:02:06.700 break that down. Epistemology is the study of 00:02:06.700 --> 00:02:09.699 knowledge, but genetic in this context doesn't 00:02:09.699 --> 00:02:12.300 mean DNA, right? It means origins or genesis. 00:02:12.599 --> 00:02:15.139 Exactly. It simply means the study of the origins 00:02:15.139 --> 00:02:18.219 and developmental trajectory of knowledge. Piaget 00:02:18.219 --> 00:02:20.199 believed that to understand how human beings 00:02:20.199 --> 00:02:23.419 think, you had to study the earliest form of 00:02:23.419 --> 00:02:25.800 that thinking. Which means studying children. 00:02:26.000 --> 00:02:27.740 Which led him straight to studying children. 00:02:27.900 --> 00:02:30.599 For him, the qualitative jump from a child's 00:02:30.599 --> 00:02:34.400 understanding of space to an adult's was a key 00:02:34.400 --> 00:02:37.259 to unlocking the construction of human rationality 00:02:37.259 --> 00:02:39.039 itself. So let's start at the very beginning, 00:02:39.199 --> 00:02:41.800 what we can maybe call the Zierolf Piaget. He 00:02:41.800 --> 00:02:45.099 was born in Neuchatel, Switzerland in 1896. His 00:02:45.099 --> 00:02:47.039 father was a professor of medieval literature. 00:02:47.419 --> 00:02:49.500 You might think he was destined for the humanities. 00:02:49.960 --> 00:02:52.439 But he was captivated by the natural world, biology 00:02:52.439 --> 00:02:54.860 in particular. He was a genuine child prodigy 00:02:54.860 --> 00:02:57.460 in the hard sciences. He developed this intense 00:02:57.460 --> 00:03:00.300 early interest in zoology and, you know, specifically 00:03:00.300 --> 00:03:03.949 mollusks. Mollusks. Yes, mosques. His reputation 00:03:03.949 --> 00:03:06.610 grew so quickly. By the time he was just 15 years 00:03:06.610 --> 00:03:08.789 old, he had published several scientific articles 00:03:08.789 --> 00:03:10.889 on these creatures. He was getting recognition 00:03:10.889 --> 00:03:13.830 from scientists across Europe who often didn't 00:03:13.830 --> 00:03:15.590 even realize they were corresponding with a teenager. 00:03:17.560 --> 00:03:20.020 He pursued this passion academically, right? 00:03:20.099 --> 00:03:22.639 He got his doctorate in 1918. He did from the 00:03:22.639 --> 00:03:25.020 University of Neuchatel. And that early immersion 00:03:25.020 --> 00:03:27.659 in biology is absolutely critical because it 00:03:27.659 --> 00:03:30.780 gives us the first major key insight into his 00:03:30.780 --> 00:03:32.879 later psychological theories. Because he spent 00:03:32.879 --> 00:03:36.120 years studying how biological organisms adapt 00:03:36.120 --> 00:03:38.580 to their environment. That's the absolute core 00:03:38.580 --> 00:03:41.300 of the connection. His entire psychological model 00:03:41.300 --> 00:03:44.939 is built on an analogy to biology. He saw cognitive 00:03:44.939 --> 00:03:47.419 development as simply an extension of that biological 00:03:47.419 --> 00:03:50.599 imperative to adapt. The mollusks adapting their 00:03:50.599 --> 00:03:53.319 shells or behaviors to changing waters. That 00:03:53.319 --> 00:03:55.539 is fundamentally the same mechanism, in his view, 00:03:55.659 --> 00:03:58.240 as the human mind adapting its mental structures 00:03:58.240 --> 00:04:01.159 to new sensory input. To bring the scientific 00:04:01.159 --> 00:04:03.879 mind down to a very human level, the sources 00:04:03.879 --> 00:04:06.099 highlight a story that shows exactly where his 00:04:06.099 --> 00:04:07.979 fascination with the construction of reality 00:04:07.979 --> 00:04:11.400 began. Ah, the famous false memory of the kidnapping. 00:04:12.090 --> 00:04:14.969 Such a telling anecdote. When he was a teenager, 00:04:15.270 --> 00:04:18.350 his family's former nanny wrote a letter. Right, 00:04:18.410 --> 00:04:21.329 a confession. A confession. She admitted that 00:04:21.329 --> 00:04:23.750 she had lied years earlier about this dramatic 00:04:23.750 --> 00:04:26.310 incident where she supposedly fought off a would 00:04:26.310 --> 00:04:29.069 -be kidnapper trying to snatch baby Jean from 00:04:29.069 --> 00:04:31.029 his fram. It never happened. The whole story 00:04:31.029 --> 00:04:33.569 was fabricated by the nanny for attention. Right. 00:04:33.959 --> 00:04:36.459 But Piaget, even after he knew for a fact that 00:04:36.459 --> 00:04:38.860 the memory was false, could still vividly recall 00:04:38.860 --> 00:04:41.600 the scene. He remembered the scar on the nanny's 00:04:41.600 --> 00:04:44.779 face, the feeling of the struggle. Wow. He was 00:04:44.779 --> 00:04:47.540 profoundly moved by the realization that a piece 00:04:47.540 --> 00:04:49.660 of knowledge, a memory of a traumatic event, 00:04:49.920 --> 00:04:52.860 could be so durable, so emotionally real, yet 00:04:52.860 --> 00:04:56.019 factually empty. This moment really sparked his 00:04:56.019 --> 00:04:58.500 lifelong dedication to understanding how we form 00:04:58.500 --> 00:05:01.100 and maintain knowledge, why some structures of 00:05:01.100 --> 00:05:02.699 knowledge persist even when they're challenged 00:05:02.699 --> 00:05:05.040 by reality. So he's trained in natural history 00:05:05.040 --> 00:05:07.459 and philosophy. He's fascinated by how reality 00:05:07.459 --> 00:05:10.339 is constructed. And then he undertakes postdoctoral 00:05:10.339 --> 00:05:13.560 work in Zurich and Paris between 1918 and 1921. 00:05:13.879 --> 00:05:16.500 He finds himself in the lab of Alfred Binet. 00:05:16.639 --> 00:05:19.259 The French psychologist famous for developing 00:05:19.259 --> 00:05:21.660 the Binet -Simon intelligence test. The first 00:05:21.660 --> 00:05:25.100 modern IQ test. That's the one. Piaget was hired 00:05:25.100 --> 00:05:28.779 in Paris in 1919 to help standardize these psychometric 00:05:28.779 --> 00:05:31.500 measures for Binet. So he was sitting there day 00:05:31.500 --> 00:05:34.459 after day, marking stacks of tests given to French 00:05:34.459 --> 00:05:37.220 children. And this is the pivotal transformative 00:05:37.220 --> 00:05:39.759 moment. Here's where it gets really interesting 00:05:39.759 --> 00:05:42.139 and where the whole field kind of pivots. Instead 00:05:42.139 --> 00:05:44.540 of just calculating the scores, Piaget started 00:05:44.540 --> 00:05:48.439 focusing on the errors, the wrong answers. Exactly. 00:05:48.439 --> 00:05:51.600 He had this crucial insight. He realized that 00:05:51.600 --> 00:05:53.899 the younger children were not just failing randomly. 00:05:54.259 --> 00:05:56.699 They were consistently making the same kinds 00:05:56.699 --> 00:05:59.550 of wrong answers. If you ask them, for example, 00:05:59.610 --> 00:06:01.850 a question about cause and effect, their faulty 00:06:01.850 --> 00:06:04.529 logic would follow a predictable non -adult pattern. 00:06:04.790 --> 00:06:07.009 Wait, so if the answers are systematically wrong, 00:06:07.129 --> 00:06:09.129 that suggests they aren't just less intelligent 00:06:09.129 --> 00:06:11.870 adults. It suggests they're operating under a 00:06:11.870 --> 00:06:14.250 totally different set of mental rules. That was 00:06:14.250 --> 00:06:17.079 the revolutionary insight. Piaget concluded that 00:06:17.079 --> 00:06:19.980 young children's cognitive processes are qualitatively 00:06:19.980 --> 00:06:22.560 and inherently different from adults. They live 00:06:22.560 --> 00:06:24.519 in a world governed by different mental structures. 00:06:24.779 --> 00:06:27.819 Which means the traditional IQ test, which only 00:06:27.819 --> 00:06:29.740 measured performance against an adult standard, 00:06:30.060 --> 00:06:32.480 was totally inadequate. Completely inadequate. 00:06:33.240 --> 00:06:36.540 What was needed, he realized, was a global theory 00:06:36.540 --> 00:06:39.420 explaining the developmental stages of those 00:06:39.420 --> 00:06:42.079 mental structures, how you get from one set of 00:06:42.079 --> 00:06:44.339 rules to the next. He takes this idea, returns 00:06:44.339 --> 00:06:47.399 to Switzerland in 1921, and becomes the director 00:06:47.399 --> 00:06:50.579 of the Rousseau Institute in Geneva. His research 00:06:50.579 --> 00:06:53.420 program explodes, but it's crucial to understand 00:06:53.420 --> 00:06:55.939 that his own theory was constantly shifting and 00:06:55.939 --> 00:06:58.600 evolving over the decades. Oh, absolutely. It 00:06:58.600 --> 00:07:03.310 wasn't a single static theory. Piaget's evolving 00:07:03.310 --> 00:07:06.089 work into four major phases, which really shows 00:07:06.089 --> 00:07:08.189 the incredible flexibility of his intellectual 00:07:08.189 --> 00:07:10.990 focus. Okay, let's walk through those. So, phase 00:07:10.990 --> 00:07:14.329 one, the sociological model. This is in the 1920s. 00:07:14.490 --> 00:07:17.629 Here, Piaget focused on the shift from egocentrism 00:07:17.629 --> 00:07:21.050 to sociocentrism. He saw social interaction as 00:07:21.050 --> 00:07:24.089 the driving force that forced a child to acknowledge 00:07:24.089 --> 00:07:26.949 viewpoints other than their own. challenging 00:07:26.949 --> 00:07:29.730 their naive initial ideas. And this is where 00:07:29.730 --> 00:07:32.269 he developed his unique research method. Yes, 00:07:32.410 --> 00:07:35.310 the revolutionary semi -clinical interview, moving 00:07:35.310 --> 00:07:38.149 away from rigid testing. And interestingly, this 00:07:38.149 --> 00:07:40.470 early work actually influenced the research design 00:07:40.470 --> 00:07:42.889 of the famous Hawthorne experiments. Then we 00:07:42.889 --> 00:07:45.410 have phase two, the biological model. This is 00:07:45.410 --> 00:07:47.230 the one we touched on earlier, where he formally 00:07:47.230 --> 00:07:49.189 connected his zoology background to psychology. 00:07:49.449 --> 00:07:51.949 He viewed intellectual development as an extension 00:07:51.949 --> 00:07:54.699 of the biological process of adaptation. This 00:07:54.699 --> 00:07:57.259 phase introduced the core duo assimilation and 00:07:57.259 --> 00:08:00.160 accommodation, the mechanisms that fuel all cognitive 00:08:00.160 --> 00:08:01.920 change. And then the one everyone knows, phase 00:08:01.920 --> 00:08:04.720 three, the logical model. Right. This is the 00:08:04.720 --> 00:08:07.720 third Piaget, the most famous one, popularized 00:08:07.720 --> 00:08:11.399 globally in the 1960s. This framework emphasizes 00:08:11.399 --> 00:08:14.220 that intelligence develops in progressive, discrete, 00:08:14.540 --> 00:08:18.379 age -related stages. The central idea here is 00:08:18.379 --> 00:08:21.240 that concepts formed in an earlier stage must 00:08:21.240 --> 00:08:23.759 be logically reconstructed at the next higher 00:08:23.759 --> 00:08:26.199 order level, forming what he described as an 00:08:26.199 --> 00:08:29.680 upward expanding spiral of complexity. And finally, 00:08:29.680 --> 00:08:33.120 his later work, Phase 4, The Study of Figurative 00:08:33.120 --> 00:08:35.519 Thought. This really demonstrated his continued 00:08:35.519 --> 00:08:38.340 intellectual curiosity. He started investigating 00:08:38.340 --> 00:08:40.960 non -logical aspects of intelligence, such as 00:08:40.960 --> 00:08:43.620 perception, images, and memory. He noted that 00:08:43.620 --> 00:08:45.940 these aspects, unlike the fully logical operations 00:08:45.940 --> 00:08:48.740 studied in Phase 3, are not completely reversible. 00:08:49.120 --> 00:08:51.179 He was acknowledging that intelligence wasn't 00:08:51.179 --> 00:08:53.559 just cold, hard logic. Okay, so let's delve into 00:08:53.559 --> 00:08:55.639 those core concepts from the biological model, 00:08:55.740 --> 00:08:57.519 because these are really the engine parts. We 00:08:57.519 --> 00:09:00.500 need to define assimilation, accommodation, and 00:09:00.500 --> 00:09:02.440 how they relate to the structure itself, the 00:09:02.440 --> 00:09:04.600 schema. Let's start with a fundamental structure, 00:09:04.799 --> 00:09:09.059 the schema or schemata in plural. Think of a 00:09:09.059 --> 00:09:13.279 schema as a mental filing cabinet or a structured 00:09:13.279 --> 00:09:15.879 cluster of concepts. It's a mental framework 00:09:15.879 --> 00:09:18.000 you create through ongoing interaction with the 00:09:18.000 --> 00:09:19.740 world. And this framework helps you interpret 00:09:19.740 --> 00:09:22.539 new information and guide your behavior. Exactly. 00:09:22.539 --> 00:09:25.500 So the schema is the container or the existing 00:09:25.500 --> 00:09:28.220 file structure in your brain. Now, how does new 00:09:28.220 --> 00:09:30.059 information get processed? It goes through that 00:09:30.059 --> 00:09:33.250 dual process of adaptation. Right. First is assimilation. 00:09:33.809 --> 00:09:36.509 This occurs when you encounter a new object or 00:09:36.509 --> 00:09:39.049 event and respond to it in a way that is consistent 00:09:39.049 --> 00:09:41.929 with an existing schema. You take the new information 00:09:41.929 --> 00:09:45.110 and you sort of force it to fit into your existing 00:09:45.110 --> 00:09:47.090 mental file structure. Let's make that concrete. 00:09:47.250 --> 00:09:49.730 An infant, for example, has a schema for sucking. 00:09:50.009 --> 00:09:52.750 Exactly. A very powerful, very early schema. 00:09:53.090 --> 00:09:55.769 So when that infant encounters any new object, 00:09:55.990 --> 00:09:58.470 a blanket corner, a toy block, their own toe, 00:09:58.710 --> 00:10:01.200 they're likely to put it in their mouth. They're 00:10:01.200 --> 00:10:03.440 assimilating all of those different objects into 00:10:03.440 --> 00:10:06.139 the existing schema of an object to be sucked. 00:10:06.320 --> 00:10:08.620 They're mentally transforming the world to conform 00:10:08.620 --> 00:10:10.860 to their existing structures. That's the key. 00:10:11.240 --> 00:10:14.500 But inevitably, that process runs into problems. 00:10:14.820 --> 00:10:17.559 If you try to suck on a complex object, say a 00:10:17.559 --> 00:10:20.559 big square block, the pure sucking reflex doesn't 00:10:20.559 --> 00:10:22.960 work very well. The world pushes back. And that 00:10:22.960 --> 00:10:26.240 conflict is essential. It's everything. When 00:10:26.240 --> 00:10:28.620 the old schema is insufficient to explain or 00:10:28.620 --> 00:10:31.159 interact with the new object, the second process, 00:10:31.460 --> 00:10:34.740 accommodation, takes over. Accommodation means 00:10:34.740 --> 00:10:37.759 modifying the existing schema or forming an entirely 00:10:37.759 --> 00:10:40.879 new one to deal with that novel object or event. 00:10:41.159 --> 00:10:42.799 So you have to change the container because the 00:10:42.799 --> 00:10:45.019 new file won't fit the old structure. That's 00:10:45.019 --> 00:10:47.419 a perfect way to put it. The infant, realizing 00:10:47.419 --> 00:10:49.740 they must adjust their tongue placement or mouth 00:10:49.740 --> 00:10:52.259 shape to effectively suck a soft bottle nipple 00:10:52.259 --> 00:10:55.820 versus a hard toy block, is accommodating. Their 00:10:55.820 --> 00:10:58.000 original reflex structure has to change to meet 00:10:58.000 --> 00:11:00.100 the demands of the complex environment. So if 00:11:00.100 --> 00:11:02.440 assimilation is warping the new thing to fit 00:11:02.440 --> 00:11:05.480 the old file, accommodation is creating a new 00:11:05.480 --> 00:11:07.820 file or warping the whole cabinet to fit the 00:11:07.820 --> 00:11:11.000 demanding new reality. Exactly. And the constant 00:11:11.000 --> 00:11:13.639 pressure to balance the conflict, the cognitive 00:11:13.639 --> 00:11:16.299 dissonance between assimilation and accommodation, 00:11:16.639 --> 00:11:19.279 provides the impetus for intellectual development. 00:11:19.740 --> 00:11:23.240 He called this process equilibration. It's a 00:11:23.240 --> 00:11:26.659 drive for balance. When a child encounters something 00:11:26.659 --> 00:11:28.679 new and fails to assimilate it successfully, 00:11:29.080 --> 00:11:32.639 they're in a state of disquilibrium. That discomfort, 00:11:32.879 --> 00:11:35.919 that moment of cognitive confusion, is what motivates 00:11:35.919 --> 00:11:38.620 them to change their schemas to accommodate until 00:11:38.620 --> 00:11:40.840 they reach a new, more stable state of equilibrium. 00:11:41.259 --> 00:11:43.159 It's like the mind is constantly trying to keep 00:11:43.159 --> 00:11:45.960 its world tidy, but reality keeps messing up 00:11:45.960 --> 00:11:48.919 the filing system, forcing an upgrade. That's 00:11:48.919 --> 00:11:51.519 it, precisely. And these upgrades build increasingly 00:11:51.519 --> 00:11:54.159 complex structures. As we touched on, Piaget 00:11:54.159 --> 00:11:56.080 identified three main categories of structures 00:11:56.080 --> 00:11:58.220 built from these schemata over time. We start 00:11:58.220 --> 00:12:00.809 with the most basic. Behavioral schemata. These 00:12:00.809 --> 00:12:03.090 are the sensory motor schemata organized patterns 00:12:03.090 --> 00:12:05.009 of physical behavior used to interact with the 00:12:05.009 --> 00:12:07.409 environment. Things like the initial reflex actions 00:12:07.409 --> 00:12:10.149 of rooting, grasping, or stepping. Then as the 00:12:10.149 --> 00:12:12.690 child matures, they develop symbolic schemata. 00:12:12.830 --> 00:12:15.610 Right. These are internal mental symbols like 00:12:15.610 --> 00:12:18.710 images, words, and verbal codes used to represent 00:12:18.710 --> 00:12:20.970 experiences. It's how you can understand the 00:12:20.970 --> 00:12:23.750 word dog without seeing an actual dog in front 00:12:23.750 --> 00:12:25.850 of you. And finally, the pinnacle of intellectual 00:12:25.850 --> 00:12:29.360 development. Operational schemata. These are 00:12:29.360 --> 00:12:31.600 the internal mental activities that are performed 00:12:31.600 --> 00:12:34.860 on objects of thought. The ability to mentally 00:12:34.860 --> 00:12:37.980 manipulate concepts. Things like solving an equation 00:12:37.980 --> 00:12:40.480 in your head or calculating the trajectory of 00:12:40.480 --> 00:12:42.879 a ball. It's this constant refinement process. 00:12:43.460 --> 00:12:46.120 Early concepts are overgeneralized, but with 00:12:46.120 --> 00:12:48.299 maturity and experience, they become more detailed. 00:12:48.840 --> 00:12:51.059 The brain is just constantly working to build 00:12:51.059 --> 00:12:53.139 and rebuild itself. So now we get to the famous 00:12:53.139 --> 00:12:55.460 four stages, the logical model that outlines 00:12:55.460 --> 00:12:57.799 how these constantly evolving schemata manifest 00:12:57.799 --> 00:13:00.320 across the lifespan. And we should remember these 00:13:00.320 --> 00:13:03.440 stages are universal and progressive. You must 00:13:03.440 --> 00:13:06.039 generally master the core concepts of one before 00:13:06.039 --> 00:13:08.580 you can fully enter the next. Yes, that sequential 00:13:08.580 --> 00:13:11.220 hierarchical nature is the bedrock of this model. 00:13:11.419 --> 00:13:14.240 Let's start with stage one, sensorimotor. This 00:13:14.240 --> 00:13:17.049 is from birth to about two years old. This is 00:13:17.049 --> 00:13:19.389 the world experienced purely through direct physical 00:13:19.389 --> 00:13:23.389 interaction. Sucking, grabbing, looking, moving. 00:13:23.570 --> 00:13:27.389 The child is, at this point, profoundly egocentric. 00:13:27.669 --> 00:13:30.610 Totally egocentric. They're essentially trapped 00:13:30.610 --> 00:13:34.509 inside their own immediate sensory world. Egocentrism 00:13:34.509 --> 00:13:37.330 here is absolute. They literally cannot distinguish 00:13:37.330 --> 00:13:39.809 between their own body and the external environment. 00:13:40.110 --> 00:13:43.059 If they can't perceive it... For them, it doesn't 00:13:43.059 --> 00:13:45.399 exist. This brings us to the crucial milestone 00:13:45.399 --> 00:13:48.700 of this stage, object permanence. This is the 00:13:48.700 --> 00:13:50.500 understanding that objects continue to exist 00:13:50.500 --> 00:13:53.039 even when they are unseen, unheard, or untouched. 00:13:53.320 --> 00:13:55.840 P .H. observed that for babies under a few months, 00:13:55.960 --> 00:13:58.340 if you hide a toy, the baby does not search for 00:13:58.340 --> 00:14:00.039 it, out of sight, out of existence. It's just 00:14:00.039 --> 00:14:02.259 gone. It's just gone. But by the later months 00:14:02.259 --> 00:14:03.960 of this stage, and certainly by the transition 00:14:03.960 --> 00:14:06.379 to the next, the child understands that the hidden 00:14:06.379 --> 00:14:09.840 toy is merely obscured, not vanished. This realization 00:14:09.840 --> 00:14:12.059 requires the child to develop a mental representation, 00:14:12.480 --> 00:14:15.100 a schema, of the object, even when the sensory 00:14:15.100 --> 00:14:18.000 data is missing. And this stage itself is broken 00:14:18.000 --> 00:14:21.460 into six substages, which shows the incredibly 00:14:21.460 --> 00:14:23.799 rapid development just in the first two years 00:14:23.799 --> 00:14:26.440 of life. It's an explosion. It starts with simple 00:14:26.440 --> 00:14:29.679 reflexes, then moves to what he called... Primary 00:14:29.679 --> 00:14:33.279 circular reactions, reproducing accidental events 00:14:33.279 --> 00:14:36.879 centered on their own body, like discovering 00:14:36.879 --> 00:14:38.799 their thumb and then repeatedly performing thumb 00:14:38.799 --> 00:14:40.980 sucking because it feels good. So it's body focused. 00:14:41.259 --> 00:14:44.080 Exactly. Then come secondary circular reactions, 00:14:44.200 --> 00:14:46.860 which are object oriented, shaking a rattle to 00:14:46.860 --> 00:14:49.440 make a sound purely for the satisfying repetition 00:14:49.440 --> 00:14:51.340 of the effect they're having on the world. Then 00:14:51.340 --> 00:14:54.000 we see the first signs of true intention with 00:14:54.000 --> 00:14:56.179 the coordination of secondary reactions. Yes. 00:14:56.240 --> 00:14:58.929 Here they perform an intentional action. to reach 00:14:58.929 --> 00:15:01.009 a goal. They might move a blanket out of the 00:15:01.009 --> 00:15:03.309 way to reach a toy that's underneath it. It's 00:15:03.309 --> 00:15:05.570 a two -step process. And then it gets more experimental. 00:15:05.870 --> 00:15:08.929 Right, with tertiary circular reactions. Here 00:15:08.929 --> 00:15:12.269 they actively explore new possibilities through 00:15:12.269 --> 00:15:15.509 trial and error, like dropping a toy from different 00:15:15.509 --> 00:15:17.529 heights just to see what happens. They become 00:15:17.529 --> 00:15:20.889 little scientists. This culminates in the internalization 00:15:20.889 --> 00:15:23.629 of schemata, where they can finally hold mental 00:15:23.629 --> 00:15:26.820 symbols, which sets the stage for language. We 00:15:26.820 --> 00:15:28.759 should pause here and address a major academic 00:15:28.759 --> 00:15:31.299 critique. The critic Kenneth Kaye acknowledged 00:15:31.299 --> 00:15:34.379 that Piaget was an unparalleled observer of these 00:15:34.379 --> 00:15:36.779 phenomena. I mean, he noticed things nobody else 00:15:36.779 --> 00:15:39.279 did. He's a master observer. But Kaye argued 00:15:39.279 --> 00:15:41.919 that Piaget relied too heavily on analogy to 00:15:41.919 --> 00:15:44.980 biological adaptation and didn't truly explain 00:15:44.980 --> 00:15:47.460 the real -time cognitive processes that were 00:15:47.460 --> 00:15:49.399 causing the development. And that's a fair point. 00:15:49.759 --> 00:15:52.320 It's a recurring theme in the critiques. Piaget 00:15:52.320 --> 00:15:54.379 was incredible at describing what the child did. 00:15:54.539 --> 00:15:56.840 They developed object permanence by X month. 00:15:57.179 --> 00:15:59.720 But he sometimes struggled to explain the underlying 00:15:59.720 --> 00:16:02.899 mental machinery, the how. Brilliant observation, 00:16:03.259 --> 00:16:05.899 but sometimes an incomplete explanation of the 00:16:05.899 --> 00:16:09.559 mechanism. Okay, let's move to stage two, preoperational, 00:16:09.659 --> 00:16:12.539 which runs from about age two to seven. This 00:16:12.539 --> 00:16:14.419 period is ushered in by language acquisition 00:16:14.419 --> 00:16:17.360 and the explosion of symbolic thought. Now the 00:16:17.360 --> 00:16:20.000 child can represent the world internally using 00:16:20.000 --> 00:16:22.960 symbols. A stick can be a horse. A finger can 00:16:22.960 --> 00:16:25.879 be a snake. This is the symbolic function substage 00:16:25.879 --> 00:16:28.700 from about ages 2 to 4. They're using symbols 00:16:28.700 --> 00:16:31.179 to represent the world, whether in play or in, 00:16:31.279 --> 00:16:33.320 you know, their crude drawings of their family. 00:16:33.519 --> 00:16:36.139 Then comes the intuitive thought substage from 00:16:36.139 --> 00:16:39.240 4 to 7. This is the endless why and how come. 00:16:39.950 --> 00:16:42.409 They are showing primitive reasoning, trying 00:16:42.409 --> 00:16:44.269 to figure out the world through pure curiosity. 00:16:44.570 --> 00:16:47.409 However, Piaget noted they operate on intuition 00:16:47.409 --> 00:16:50.049 and feelings rather than logic, and they can't 00:16:50.049 --> 00:16:51.850 explain how they acquired the knowledge they 00:16:51.850 --> 00:16:54.809 are so curious about. Their thinking is still, 00:16:54.990 --> 00:16:57.980 as he put it, sparse and inadequate for true 00:16:57.980 --> 00:17:00.360 mental operations. And this stage is famously 00:17:00.360 --> 00:17:03.100 defined by its limitations, the major hurdles 00:17:03.100 --> 00:17:04.920 the child has to overcome to become a logical 00:17:04.920 --> 00:17:07.559 thinker. The first major limitation is still 00:17:07.559 --> 00:17:09.819 egocentrism, but it's evolved from the total 00:17:09.819 --> 00:17:13.579 egocentrism of infancy. Right. The preoperational 00:17:13.579 --> 00:17:15.640 child now knows they are separate from the world, 00:17:15.799 --> 00:17:18.420 but they still struggle profoundly with seeing 00:17:18.420 --> 00:17:20.740 the world from any viewpoint other than their 00:17:20.740 --> 00:17:23.589 own. Piaget famously demonstrated this with the 00:17:23.589 --> 00:17:25.950 three mountains task. Describe that task for 00:17:25.950 --> 00:17:28.529 us because it perfectly encapsulates the preoperational 00:17:28.529 --> 00:17:31.910 mindset. So Piaget would place a child on one 00:17:31.910 --> 00:17:34.910 side of a table and arrange three model mountains 00:17:34.910 --> 00:17:37.670 of varying sizes on that table. He would then 00:17:37.670 --> 00:17:39.730 place a doll at different positions around the 00:17:39.730 --> 00:17:42.089 mountains. Okay. He would then ask the child 00:17:42.089 --> 00:17:45.829 to describe or to select a picture showing what 00:17:45.829 --> 00:17:48.690 the doll saw from its position. And the young 00:17:48.690 --> 00:17:51.329 pre -operational child would consistently choose 00:17:51.329 --> 00:17:53.250 the picture that showed the mountains from their 00:17:53.250 --> 00:17:55.730 own perspective. They couldn't mentally put themselves 00:17:55.730 --> 00:17:57.990 in the doll's shoes? They couldn't perform that 00:17:57.990 --> 00:18:00.690 mental transformation. They simply cannot understand 00:18:00.690 --> 00:18:02.890 that the doll's view was obstructed or different. 00:18:03.130 --> 00:18:05.130 That makes the world incredibly difficult to 00:18:05.130 --> 00:18:07.750 navigate socially and logically. And the second 00:18:07.750 --> 00:18:10.990 crucial limitation is irreversible thought and 00:18:10.990 --> 00:18:13.740 its partner, centration. Irreversible thought 00:18:13.740 --> 00:18:16.559 is the inability to mentally return an item or 00:18:16.559 --> 00:18:20.460 a situation to its original state. And centration 00:18:20.460 --> 00:18:22.960 is the tendency to focus on only one striking 00:18:22.960 --> 00:18:25.960 feature of an object or situation while ignoring 00:18:25.960 --> 00:18:28.279 all the other attributes. And this pair of limitations 00:18:28.279 --> 00:18:31.079 leads directly to the famous beaker conservation 00:18:31.079 --> 00:18:34.779 task. This is perhaps Piaget's most iconic demonstration. 00:18:35.160 --> 00:18:37.640 Absolutely. So the child is presented with two 00:18:37.640 --> 00:18:41.299 identical, short, wide beakers, both filled with 00:18:41.299 --> 00:18:43.220 the same amount of liquid. The child confirms, 00:18:43.460 --> 00:18:47.079 yes, they are equal. Then, the experimenter pours 00:18:47.079 --> 00:18:49.200 the liquid from one of the short beakers into 00:18:49.200 --> 00:18:52.200 a third beaker that is very tall and thin. So 00:18:52.200 --> 00:18:54.640 the liquid level is now much higher in the tall, 00:18:54.700 --> 00:18:56.779 thin beaker, but the quantity is exactly the 00:18:56.779 --> 00:19:00.019 same. Right. But the preoperational child, restricted 00:19:00.019 --> 00:19:03.259 by centration, fails the conservation test. They 00:19:03.259 --> 00:19:05.380 look at the two remaining beakers, the short, 00:19:05.380 --> 00:19:07.859 full one and the tall, thin one, and they insist 00:19:07.859 --> 00:19:10.789 that the tall, thin beaker has more liquid because 00:19:10.789 --> 00:19:12.910 they're stuck on one feature they are focusing 00:19:12.910 --> 00:19:15.630 or centrating only on the height of the liquid 00:19:15.630 --> 00:19:18.190 column the most perceptually striking feature 00:19:18.190 --> 00:19:21.789 and ignoring the change in width and crucially 00:19:21.789 --> 00:19:25.210 because of irreversible thought they cannot mentally 00:19:25.210 --> 00:19:27.730 reverse the action and imagine pouring the liquid 00:19:27.730 --> 00:19:30.670 back into the original short wide beaker to prove 00:19:30.670 --> 00:19:33.470 the quantities are equal that's a powerful illustration 00:19:33.470 --> 00:19:36.609 of the difference in mental machinery this finally 00:19:36.609 --> 00:19:39.380 gets resolved in stage three Concrete operational, 00:19:39.779 --> 00:19:42.880 which runs from about ages 7 to 11. This is a 00:19:42.880 --> 00:19:46.160 major structural leap. Children gain the ability 00:19:46.160 --> 00:19:48.859 to perform true mental operations, but they remain 00:19:48.859 --> 00:19:51.420 anchored to physical reality, to the concrete. 00:19:51.599 --> 00:19:53.859 They become aware of logic, and they are finally 00:19:53.859 --> 00:19:55.759 decentered, so they're no longer egocentric. 00:19:55.960 --> 00:19:58.079 The conservation hurdle is overcome here, right? 00:19:58.160 --> 00:20:01.109 Yes. They now understand conservation. That quantity 00:20:01.109 --> 00:20:03.130 remains the same despite changes in appearance. 00:20:03.569 --> 00:20:05.670 They understand the reversibility principle. 00:20:05.930 --> 00:20:08.150 If you can mentally reverse the pouring action 00:20:08.150 --> 00:20:10.450 in the beaker task, the quantities must be equal. 00:20:10.690 --> 00:20:13.190 They also develop strong classification skills 00:20:13.190 --> 00:20:16.170 and transitive reasoning. You know, if A is bigger 00:20:16.170 --> 00:20:18.950 than B and B is bigger than C, then A must be 00:20:18.950 --> 00:20:21.769 bigger than C. Exactly. But the limitation is 00:20:21.769 --> 00:20:24.210 still that word concrete. They can apply these 00:20:24.210 --> 00:20:27.329 logical principles only to things they can physically 00:20:27.329 --> 00:20:31.079 manipulate, see, or touch. Asking them to solve 00:20:31.079 --> 00:20:33.819 a completely abstract, hypothetical problem without 00:20:33.819 --> 00:20:36.299 a real -world anchor remains very difficult. 00:20:36.480 --> 00:20:39.579 Which brings us to stage four, formal operational. 00:20:40.220 --> 00:20:42.759 beginning around age 11 and continuing onward. 00:20:42.960 --> 00:20:45.740 This is the final stage, marked by the arrival 00:20:45.740 --> 00:20:49.559 of true abstract reasoning. This allows for hypothetical 00:20:49.559 --> 00:20:51.720 scenarios for counterfactuals for philosophy. 00:20:51.960 --> 00:20:54.839 They develop what Puget called hypothetical deductive 00:20:54.839 --> 00:20:57.200 reasoning. They can think systematically about 00:20:57.200 --> 00:20:59.819 abstract concepts like justice, infinity, or 00:20:59.819 --> 00:21:01.759 morality. They can also think about their own 00:21:01.759 --> 00:21:04.269 thinking? Yes, they use metacognition, they think 00:21:04.269 --> 00:21:06.130 about their own thinking processes, and they 00:21:06.130 --> 00:21:08.190 can display multi -step problem -solving skills, 00:21:08.430 --> 00:21:11.150 isolating variables and complex problems in a 00:21:11.150 --> 00:21:12.890 way that would have been impossible in the concrete 00:21:12.890 --> 00:21:15.730 operational stage. This is the full cognitive 00:21:15.730 --> 00:21:18.049 structure of the adult mind, ready to engage 00:21:18.049 --> 00:21:20.890 with the world of pure ideas. We have the stages, 00:21:20.970 --> 00:21:23.710 but as we established, PJ was constantly evolving. 00:21:24.150 --> 00:21:26.769 Early critics often felt he characterized the 00:21:26.769 --> 00:21:29.509 preoperational child a bit unfairly by focusing 00:21:29.509 --> 00:21:33.160 only on what they lacked. like conservation and 00:21:33.160 --> 00:21:36.319 reversibility. His later career work sought to 00:21:36.319 --> 00:21:38.200 understand the competencies they did possess. 00:21:38.539 --> 00:21:41.359 This is his late turn. He started shifting from 00:21:41.359 --> 00:21:43.920 the rigid stage model to focusing on the mechanics 00:21:43.920 --> 00:21:46.640 of functions and correspondences. And this work 00:21:46.640 --> 00:21:49.500 suggested greater developmental continuity, acknowledging 00:21:49.500 --> 00:21:51.960 that children possessed many skills before they 00:21:51.960 --> 00:21:54.420 reached the designated stage for logic. Let's 00:21:54.420 --> 00:21:56.400 break down functions first. When he talks about 00:21:56.400 --> 00:21:58.099 functions, he's talking about relationships, 00:21:58.400 --> 00:22:01.039 right? A mapping from one set of things to another. 00:22:01.440 --> 00:22:04.440 Precisely. He described functions as being univocal 00:22:04.440 --> 00:22:08.119 to the right, meaning for every input in X, there 00:22:08.119 --> 00:22:11.390 is exactly one output in Y. He was looking for 00:22:11.390 --> 00:22:13.569 a kind of pre -logical understanding of these 00:22:13.569 --> 00:22:15.529 ordered relationships in young children. Can 00:22:15.529 --> 00:22:18.269 you give us a practical example of how a preoperational 00:22:18.269 --> 00:22:21.309 child might demonstrate this simological comparison? 00:22:21.950 --> 00:22:24.410 Okay, think about array length. If you show a 00:22:24.410 --> 00:22:27.609 child two rows of items, say 10 pennies in one 00:22:27.609 --> 00:22:30.490 row spaced far apart and 10 pennies in a second 00:22:30.490 --> 00:22:33.069 row spaced close together, the preoperational 00:22:33.069 --> 00:22:36.460 child often says the longer row has more. Which 00:22:36.460 --> 00:22:39.279 is a classic conservation error. It is, and it's 00:22:39.279 --> 00:22:41.839 often rooted in centration. But it also shows 00:22:41.839 --> 00:22:44.319 an early flawed attempt at functional reasoning. 00:22:44.720 --> 00:22:47.240 They are using the perceptual function of length 00:22:47.240 --> 00:22:50.220 to index the concept of quantity. They are seeing 00:22:50.220 --> 00:22:53.259 a one -directional relationship. Length equals 00:22:53.259 --> 00:22:55.759 quantity. It's an imperfect semiological comparison, 00:22:56.039 --> 00:22:58.579 but it's a form of structural reasoning. That's 00:22:58.579 --> 00:23:01.720 clearer. And what about correspondences or morphisms? 00:23:01.940 --> 00:23:04.200 How did he test those structural relationships? 00:23:04.759 --> 00:23:07.000 He designed these ingenious hands -on tests. 00:23:07.240 --> 00:23:09.880 One involved children matching movable red cutouts 00:23:09.880 --> 00:23:12.299 to a base card that was segmented with both red 00:23:12.299 --> 00:23:14.940 and white areas. The child's goal was to cover 00:23:14.940 --> 00:23:16.920 the white areas perfectly so the entire base 00:23:16.920 --> 00:23:19.680 card appeared red. So it's a spatial puzzle that's 00:23:19.680 --> 00:23:22.680 really about structural matching? Exactly. And 00:23:22.680 --> 00:23:24.559 he found that the youngest children he studied 00:23:24.559 --> 00:23:27.740 around age five could successfully match one 00:23:27.740 --> 00:23:30.339 cut -out piece to one corresponding base section 00:23:30.339 --> 00:23:33.980 using trial and error. This is a one -to -one 00:23:33.980 --> 00:23:37.079 match, which he called bejection, or term -by 00:23:37.079 --> 00:23:39.420 -term correspondence. They could see the individual 00:23:39.420 --> 00:23:42.180 pieces fitting together. Right. But as they got 00:23:42.180 --> 00:23:45.049 older... their ability to handle complexity increased. 00:23:45.470 --> 00:23:47.950 The older children were able to solve the puzzle 00:23:47.950 --> 00:23:50.170 even when it required using three different cutouts 00:23:50.170 --> 00:23:52.809 to cover a single base card area. So a three 00:23:52.809 --> 00:23:54.730 -to -one match? A three -to -one match, which 00:23:54.730 --> 00:23:57.509 he termed surjection. This showed that knowledge 00:23:57.509 --> 00:24:00.329 wasn't just being acquired. The structural relationship 00:24:00.329 --> 00:24:02.789 they understood, the ability to map multiple 00:24:02.789 --> 00:24:04.970 inputs onto a single output, was developing. 00:24:05.589 --> 00:24:08.009 Piaget argued this knowledge emerges from increasingly 00:24:08.009 --> 00:24:10.849 refined, primitive applications of action schemes 00:24:10.849 --> 00:24:13.470 on objects in the environment. The beauty of 00:24:13.470 --> 00:24:15.890 this later work is that it acknowledges the immense 00:24:15.890 --> 00:24:18.329 complexity of childhood thought, rather than 00:24:18.329 --> 00:24:21.410 just categorizing their failures. But to observe 00:24:21.410 --> 00:24:23.930 these nuances, Piaget had to completely reinvent 00:24:23.930 --> 00:24:27.069 the way he gathered data. He was deeply dissatisfied 00:24:27.069 --> 00:24:30.049 with traditional methods, like Binet's psychometric 00:24:30.049 --> 00:24:33.269 tests. He found them far too rigid. You know, 00:24:33.269 --> 00:24:35.789 you ask the question, the child answers, and 00:24:35.789 --> 00:24:38.009 you move on. You don't get to the child's deepest 00:24:38.009 --> 00:24:40.329 thoughts. You can't tell if they really believe 00:24:40.329 --> 00:24:43.119 what they're saying. Exactly. He couldn't discern 00:24:43.119 --> 00:24:45.319 if the child truly believed what they said or 00:24:45.319 --> 00:24:47.380 if they were just parroting an adult or pretending. 00:24:47.900 --> 00:24:50.819 So he moved away from standardized testing and 00:24:50.819 --> 00:24:53.259 pioneered the semi -clinical interview. And that 00:24:53.259 --> 00:24:55.759 was, I mean, that was a complete game changer 00:24:55.759 --> 00:24:58.559 for how research was done. A revolutionary methodological 00:24:58.559 --> 00:25:02.140 shift. It was dynamic, flexible, and iterative. 00:25:02.920 --> 00:25:05.700 Pichet would start with a general question, but 00:25:05.700 --> 00:25:07.680 then his subsequent questions would be entirely 00:25:07.680 --> 00:25:10.700 based on the child's response. He carefully monitored 00:25:10.700 --> 00:25:13.259 their speech patterns, their body language, all 00:25:13.259 --> 00:25:16.839 these behavioral cues in a comfortable, non -threatening 00:25:16.839 --> 00:25:19.759 environment to elicit what he called spontaneous 00:25:19.759 --> 00:25:22.099 conviction. He was trying to get inside their 00:25:22.099 --> 00:25:25.180 operational schema. Precisely. Instead of just 00:25:25.180 --> 00:25:27.940 testing what they knew, he was testing how they 00:25:27.940 --> 00:25:30.980 knew it. A classic example of an abstract question 00:25:30.980 --> 00:25:33.019 he might use to investigate the child's thinking 00:25:33.019 --> 00:25:35.700 process, rather than the content of their thought, 00:25:35.859 --> 00:25:39.950 was simply, Can you see a thought? The child's 00:25:39.950 --> 00:25:42.309 reasoning, regardless of the answer, was the 00:25:42.309 --> 00:25:45.250 data point. To really drive home how complex 00:25:45.250 --> 00:25:47.849 this development is, even within a single stage, 00:25:48.130 --> 00:25:51.569 let's revisit the conservation challenge. This 00:25:51.569 --> 00:25:54.210 one provided a surprising counterintuitive finding 00:25:54.210 --> 00:25:57.430 that actually complicated his own stage theory. 00:25:57.789 --> 00:26:00.450 This was the study involving two lines of sweets. 00:26:00.690 --> 00:26:03.049 He studied children between two and a half and 00:26:03.049 --> 00:26:05.049 four and a half years old, right in the preoperational 00:26:05.049 --> 00:26:07.720 stage. He presented two rows of sweets, both 00:26:07.720 --> 00:26:10.160 containing the exact same number, but one row 00:26:10.160 --> 00:26:11.940 was spread farther apart, making it visually 00:26:11.940 --> 00:26:14.880 longer. So the expected finding, based on centration, 00:26:15.000 --> 00:26:17.099 would be that all children in that stage would 00:26:17.099 --> 00:26:19.680 choose the longer row. They'd all fail. But the 00:26:19.680 --> 00:26:22.480 finding was unexpected and very nuanced. Children 00:26:22.480 --> 00:26:24.700 younger than three years and two months actually 00:26:24.700 --> 00:26:26.960 correctly discriminated quantity conservation. 00:26:27.420 --> 00:26:29.980 They saw both rows had the same amount. Wait, 00:26:30.019 --> 00:26:32.720 the youngest ones got it right? They did. But 00:26:32.720 --> 00:26:35.079 then older children... Up to four and a half 00:26:35.079 --> 00:26:37.700 years would indicate the longer row had more. 00:26:37.900 --> 00:26:40.660 So they regress. They get older and temporarily 00:26:40.660 --> 00:26:44.000 get worse at judging quantity. That is genuinely 00:26:44.000 --> 00:26:45.859 bizarre to think that temporary intellectual 00:26:45.859 --> 00:26:48.400 regression is a documented part of development. 00:26:48.700 --> 00:26:51.960 It's a great humbling reminder of how nonlinear 00:26:51.960 --> 00:26:55.160 learning is. It is so counterintuitive, but the 00:26:55.160 --> 00:26:58.420 analysis is key. The logical capacity for simple 00:26:58.420 --> 00:27:00.980 conservation seems to exist earlier in the younger 00:27:00.980 --> 00:27:03.660 group, perhaps due to less cognitive clutter. 00:27:04.089 --> 00:27:07.069 But as the child ages slightly, they develop 00:27:07.069 --> 00:27:09.890 strong perceptual strategies. They learn to rely 00:27:09.890 --> 00:27:13.029 heavily on visual cues. So the longer line looks 00:27:13.029 --> 00:27:15.410 like more candy. Exactly. They become temporarily 00:27:15.410 --> 00:27:17.750 handicapped by their developing perceptual dependence, 00:27:18.009 --> 00:27:20.109 and there's still limited ability to mentally 00:27:20.109 --> 00:27:23.069 reverse the situation. Only when explicit counting 00:27:23.069 --> 00:27:26.250 skills emerge reliably around age five does the 00:27:26.250 --> 00:27:28.369 conservation ability solidify and overcome that 00:27:28.369 --> 00:27:30.839 perceptual trap. It's a great example of how 00:27:30.839 --> 00:27:33.160 performance on a task is not always a perfect 00:27:33.160 --> 00:27:35.200 reflection of underlying cognitive capacity. 00:27:35.519 --> 00:27:38.759 So, what does this all mean? How did this incredibly 00:27:38.759 --> 00:27:41.660 detailed, stage -based view of childhood thought 00:27:41.660 --> 00:27:45.460 reshape the world? The influence stretches far, 00:27:45.480 --> 00:27:47.839 far beyond the confines of clinical psychology. 00:27:48.180 --> 00:27:51.279 Most significantly, his theory gave rise to the 00:27:51.279 --> 00:27:54.299 learner -centered constructivist approach that 00:27:54.299 --> 00:27:56.759 completely revolutionized education throughout 00:27:56.759 --> 00:28:00.000 the 1970s and 80s, particularly in North America 00:28:00.000 --> 00:28:02.099 and Europe. This flipped the traditional model 00:28:02.099 --> 00:28:04.380 on its head. Instead of the teacher being the 00:28:04.380 --> 00:28:06.720 sole source of truth, the vessel pouring knowledge 00:28:06.720 --> 00:28:09.299 into empty students, the student is now seen 00:28:09.299 --> 00:28:11.700 as the active builder, the architect of their 00:28:11.700 --> 00:28:14.039 own knowledge. That's the core of constructivism. 00:28:14.339 --> 00:28:17.119 PyJet defined knowledge not as passive reception, 00:28:17.339 --> 00:28:20.400 but as the ability to modify, transform, and 00:28:20.400 --> 00:28:24.009 operate on. an object or idea. The ability to 00:28:24.009 --> 00:28:26.410 transform and assimilate information actively 00:28:26.410 --> 00:28:29.369 requires a matured mental capacity. Learning 00:28:29.369 --> 00:28:31.829 is a function of active experience. This directly 00:28:31.829 --> 00:28:34.670 validates the concept of readiness. If a child's 00:28:34.670 --> 00:28:36.869 operational schemata haven't matured to the appropriate 00:28:36.869 --> 00:28:39.349 cognitive stage, say they're preoperational, 00:28:39.490 --> 00:28:41.509 then teaching them highly abstract concepts that 00:28:41.509 --> 00:28:44.009 algebra will be ineffective, even futile. Right. 00:28:44.410 --> 00:28:47.710 Learning must be tailored and built upon simpler 00:28:47.710 --> 00:28:50.609 existing operational abilities. And we see this 00:28:50.609 --> 00:28:52.849 reflected everywhere in modern curriculum design. 00:28:53.089 --> 00:28:55.650 Think about how a teacher utilizes the abilities 00:28:55.650 --> 00:28:58.369 gained in the concrete operational stage reversibility 00:28:58.369 --> 00:29:01.509 and decentration to structure lessons. A great 00:29:01.509 --> 00:29:04.309 practical example is teaching a concrete operational 00:29:04.309 --> 00:29:07.750 child vocabulary. A teacher gives a multi -step 00:29:07.750 --> 00:29:11.089 assignment. Read the word, write it, define it. 00:29:11.400 --> 00:29:14.420 and use it in a sentence that child having achieved 00:29:14.420 --> 00:29:16.700 reversibility can understand the organization 00:29:16.700 --> 00:29:19.759 and recall the steps in any order and crucially 00:29:19.759 --> 00:29:22.339 they are using decentration the ability to focus 00:29:22.339 --> 00:29:25.220 on multiple components simultaneously that allows 00:29:25.220 --> 00:29:27.599 them to identify the word recall its definition 00:29:27.599 --> 00:29:29.859 and focus on constructing the sentence all at 00:29:29.859 --> 00:29:32.660 once A pre -operational child struggles immensely 00:29:32.660 --> 00:29:35.640 because they get fixed or centrated on one step 00:29:35.640 --> 00:29:38.019 and cannot mentally backtrack. Or even a simpler 00:29:38.019 --> 00:29:40.740 example, a preschooler using a banana as a phone 00:29:40.740 --> 00:29:43.019 in symbolic play. A perfect example. They're 00:29:43.019 --> 00:29:45.119 engaging in decentration by holding two concepts, 00:29:45.359 --> 00:29:47.859 banana and phone, in their mind at the same time. 00:29:48.039 --> 00:29:50.799 Beyond pedagogy, Peja had these radical ideas 00:29:50.799 --> 00:29:53.440 about morality. He believed children construct 00:29:53.440 --> 00:29:55.940 their own moral worldview in progressive stages, 00:29:56.240 --> 00:29:58.980 and these views are often maintained autonomously, 00:29:59.140 --> 00:30:02.339 even against the wishes of adults. For his time, 00:30:02.420 --> 00:30:05.519 this was a highly radical proposition. Drawing 00:30:05.519 --> 00:30:08.359 on Kantian philosophy, Piaget argued that moral 00:30:08.359 --> 00:30:11.200 concepts like equality, reciprocity, and justice 00:30:11.200 --> 00:30:13.559 developed primarily out of peer interaction, 00:30:13.839 --> 00:30:16.359 not from instruction by authority figures. So 00:30:16.359 --> 00:30:18.819 peers were the key. Peers were the furnace where 00:30:18.819 --> 00:30:22.160 true moral reasoning was forged. He formalized 00:30:22.160 --> 00:30:24.319 this by distinguishing between two types of social 00:30:24.319 --> 00:30:26.980 relationships that shape moral growth. Okay, 00:30:27.079 --> 00:30:29.539 what were they? First, he identified asymmetrical 00:30:29.539 --> 00:30:32.059 relationships. These are characterized by constraint, 00:30:32.319 --> 00:30:34.799 typically involving adult authority, a parent 00:30:34.799 --> 00:30:37.200 or a teacher over the child. Knowledge acquired 00:30:37.200 --> 00:30:39.900 here is often fixed, dogmatic, and inflexible. 00:30:40.380 --> 00:30:42.460 Morality in this domain is often rule -based 00:30:42.460 --> 00:30:44.839 and absolute. And the second type, the one he 00:30:44.839 --> 00:30:47.519 believed was key to higher morality. The cooperative 00:30:47.519 --> 00:30:49.960 or symmetrical relations, typically established 00:30:49.960 --> 00:30:52.539 between peers, where power is evenly distributed. 00:30:52.799 --> 00:30:55.160 These conditions are necessary for authentic 00:30:55.160 --> 00:30:57.839 intellectual and moral exchange. When children 00:30:57.839 --> 00:31:00.299 have to negotiate rules for a game or resolve 00:31:00.299 --> 00:31:02.900 a conflict with a friend, the solution is regulated 00:31:02.900 --> 00:31:05.160 by the logic of argument and mutual respect, 00:31:05.400 --> 00:31:08.740 not external authority. So it's in that domain 00:31:08.740 --> 00:31:11.240 that constructive moral solutions and flexible 00:31:11.240 --> 00:31:14.259 operations emerge. Exactly. And that structural 00:31:14.259 --> 00:31:16.880 framework, the movement from externally constrained 00:31:16.880 --> 00:31:19.880 morality to autonomously negotiated morality, 00:31:20.220 --> 00:31:23.160 directly influenced Lawrence Kohlberg's highly 00:31:23.160 --> 00:31:25.960 influential stages of moral development. The 00:31:25.960 --> 00:31:28.740 legacy is crystal clear. And if we look outside 00:31:28.740 --> 00:31:31.240 psychology entirely, Piaget's structuralist and 00:31:31.240 --> 00:31:33.700 constructivist approaches left these indelible 00:31:33.700 --> 00:31:36.579 marks in some really surprising fields. Oh, absolutely. 00:31:36.779 --> 00:31:38.960 Like computing. This is one of my favorite takeaways. 00:31:39.160 --> 00:31:41.019 The creator of the logo programming language, 00:31:41.220 --> 00:31:44.039 Seymour Papert, directly credited Piaget's work 00:31:44.039 --> 00:31:46.000 for his educational approach. And it goes even 00:31:46.000 --> 00:31:49.500 deeper than that. Much deeper. Alan Kay, one 00:31:49.500 --> 00:31:53.180 of the great visionaries at Xerox PRRC, the birthplace 00:31:53.180 --> 00:31:56.400 of the modern computing environment. based the 00:31:56.400 --> 00:31:58.519 concept for his Dynabook programming system, 00:31:58.619 --> 00:32:01.099 which was the foundational idea for the modern 00:32:01.099 --> 00:32:04.500 graphical user interface, the GUI. He based that 00:32:04.500 --> 00:32:07.480 on Piaget. He based it directly on Piaget's theories 00:32:07.480 --> 00:32:10.039 of how children interact with symbols and knowledge 00:32:10.039 --> 00:32:12.799 structures. The idea that a user should actively 00:32:12.799 --> 00:32:15.680 manipulate graphical objects on a screen rather 00:32:15.680 --> 00:32:19.740 than passively type commands is rooted in Piagetian 00:32:19.740 --> 00:32:23.079 constructivism. That is massive reach, from mollusks 00:32:23.079 --> 00:32:25.380 to the desktop computer. And look at philosophy. 00:32:25.839 --> 00:32:27.880 Jürgen Habermas, the massive figure in social 00:32:27.880 --> 00:32:30.420 and political theory, incorporated Piaget's developmental 00:32:30.420 --> 00:32:32.720 structures into his theories of communicative 00:32:32.720 --> 00:32:35.089 action. And Thomas Kuhn. Of the structure of 00:32:35.089 --> 00:32:37.250 scientific revolutions. That's the one. He credited 00:32:37.250 --> 00:32:39.049 Piaget with helping him understand the nature 00:32:39.049 --> 00:32:41.609 of paradigm shifts, that sudden jump when an 00:32:41.609 --> 00:32:43.549 entire community transitions from one mode of 00:32:43.549 --> 00:32:45.109 thought, one operational structure to another. 00:32:45.809 --> 00:32:48.109 Piaget provided the psychological mechanism for 00:32:48.109 --> 00:32:50.369 that intellectual restructuring. It's even been 00:32:50.369 --> 00:32:53.079 applied to archaeology. Analyzing ancient tools, 00:32:53.240 --> 00:32:55.460 like the more complex Acheulean tools versus 00:32:55.460 --> 00:32:58.700 the simpler Oldowan tools, has been done by archaeologists 00:32:58.700 --> 00:33:01.119 like Thomas Wynne based on the spatial relationship 00:33:01.119 --> 00:33:04.660 insight required to create each kind. It's a 00:33:04.660 --> 00:33:07.059 lens for understanding nonverbal human intelligence 00:33:07.059 --> 00:33:10.839 across history. Given the sheer scope and ambition 00:33:10.839 --> 00:33:13.299 of Piaget's theory, it's inevitable that it has 00:33:13.299 --> 00:33:16.000 drawn rigorous criticism, especially as psychological 00:33:16.000 --> 00:33:18.539 tools and brain imaging became more sophisticated. 00:33:19.170 --> 00:33:21.569 Let's start with the issues surrounding his methodology, 00:33:21.869 --> 00:33:24.750 which by today's standards look quite flawed. 00:33:24.950 --> 00:33:27.589 By modern scientific standards, his research 00:33:27.589 --> 00:33:29.730 methods were highly problematic. The primary 00:33:29.730 --> 00:33:31.950 criticism centers on his reliance on incredibly 00:33:31.950 --> 00:33:35.130 small, non -random samples. As we mentioned, 00:33:35.250 --> 00:33:36.950 his foundational work, The Origins of Intelligence 00:33:36.950 --> 00:33:39.589 in Children, was based almost entirely on observing 00:33:39.589 --> 00:33:42.069 and interacting with only his own three children. 00:33:42.400 --> 00:33:44.500 Which is an extremely small, highly educated, 00:33:44.640 --> 00:33:46.960 and culturally specific group to generalize across 00:33:46.960 --> 00:33:50.519 the entire global population. Precisely. Furthermore, 00:33:50.799 --> 00:33:53.539 the methodology lacked standardization and inter 00:33:53.539 --> 00:33:56.420 -rater reliability. He would often rely on his 00:33:56.420 --> 00:33:58.960 own handwritten, highly subjective notes for 00:33:58.960 --> 00:34:01.339 analysis. And because the clinical method was 00:34:01.339 --> 00:34:03.779 so flexible, the questions asked were rarely 00:34:03.779 --> 00:34:06.279 identical between children. which makes true 00:34:06.279 --> 00:34:09.179 comparison and replication very difficult. And 00:34:09.179 --> 00:34:11.500 critics found that small changes to his procedures 00:34:11.500 --> 00:34:14.420 led to different results. They did. Whether in 00:34:14.420 --> 00:34:16.559 the object permanence tests or the conservation 00:34:16.559 --> 00:34:19.820 tasks, small tweaks often led to wildly different 00:34:19.820 --> 00:34:22.260 results, which undermined the rigidity of his 00:34:22.260 --> 00:34:25.019 stage definitions. And the concern here is that 00:34:25.019 --> 00:34:27.659 he might have simply underestimated what children 00:34:27.659 --> 00:34:29.940 were capable of because the way he presented 00:34:29.940 --> 00:34:32.800 the task confused them. That's the core linguistic 00:34:32.800 --> 00:34:35.489 and contextual critique. championed by people 00:34:35.489 --> 00:34:38.210 like Linda Siegel. Critics argued that Piaz failed 00:34:38.210 --> 00:34:40.329 to control adequately for the social context 00:34:40.329 --> 00:34:43.010 and, crucially, the children's understanding 00:34:43.010 --> 00:34:45.659 of the test language. If you ask a four -year 00:34:45.659 --> 00:34:47.940 -old the conservation question twice, which one 00:34:47.940 --> 00:34:50.539 has more, now which one has more, the child assumes 00:34:50.539 --> 00:34:52.519 the adult must want a different answer the second 00:34:52.519 --> 00:34:55.440 time. So they change their answer not because 00:34:55.440 --> 00:34:57.239 they don't understand conservation, but because 00:34:57.239 --> 00:34:59.320 they're trying to figure out what the adult wants. 00:34:59.679 --> 00:35:02.440 Exactly. It suggests performance failure was 00:35:02.440 --> 00:35:05.619 often due to social confusion or semantic misunderstanding, 00:35:06.139 --> 00:35:09.349 not a fundamental cognitive deficiency. Moving 00:35:09.349 --> 00:35:12.329 to the theoretical realm, if Piaget is the founder 00:35:12.329 --> 00:35:14.989 of developmental psychology, his most significant 00:35:14.989 --> 00:35:17.389 historical challenge comes from his contemporary, 00:35:17.730 --> 00:35:21.110 the Russian psychologist Lev Vygotsky. Vygotsky 00:35:21.110 --> 00:35:23.750 directly challenged the successive hierarchical 00:35:23.750 --> 00:35:27.130 nature of Piaget's stages. He argued that development 00:35:27.130 --> 00:35:30.190 is not purely an endogenous biological unfolding. 00:35:30.429 --> 00:35:33.710 He stressed that culture, history, and, most 00:35:33.710 --> 00:35:35.730 importantly, social interaction with others, 00:35:35.829 --> 00:35:38.679 fundamentally shape cognition. This means the 00:35:38.679 --> 00:35:41.099 idea that a child must wait until their internal 00:35:41.099 --> 00:35:43.539 mental structures are ready is challenged by 00:35:43.539 --> 00:35:45.739 Vygotsky's focus on outside help accelerating 00:35:45.739 --> 00:35:49.639 development. Precisely. Vygotsky introduced the 00:35:49.639 --> 00:35:53.699 Zone of Proximal Development, or ZPD. The ZPD 00:35:53.699 --> 00:35:55.400 is the difference between what a child can achieve 00:35:55.400 --> 00:35:57.599 independently and what they can achieve with 00:35:57.599 --> 00:36:00.199 guidance and collaboration from a more knowledgeable 00:36:00.199 --> 00:36:03.739 peer or adult. This scaffolding, which Piaget 00:36:03.739 --> 00:36:06.820 largely overlooked, suggests that cognitive capacity 00:36:06.820 --> 00:36:10.079 is less rigid and far more responsive to cultural 00:36:10.079 --> 00:36:13.260 and social forces than Piaget allowed. We also 00:36:13.260 --> 00:36:15.420 have the neo -Piagetians, who generally accepted 00:36:15.420 --> 00:36:17.780 the stage progression but felt Piaget didn't 00:36:17.780 --> 00:36:19.780 provide enough mechanical explanation for the 00:36:19.780 --> 00:36:22.000 transitions. They argued that Piaget focused 00:36:22.000 --> 00:36:24.760 too much on logical structures and not enough 00:36:24.760 --> 00:36:27.199 on the underlying mechanisms of information processing. 00:36:27.769 --> 00:36:30.989 They pointed to crucial cognitive resources like 00:36:30.989 --> 00:36:32.969 the speed of processing information, working 00:36:32.969 --> 00:36:36.130 memory capacity, and attention span as the true 00:36:36.130 --> 00:36:38.269 drivers behind stage transitions and individual 00:36:38.269 --> 00:36:40.469 differences. So for them, a child moves from 00:36:40.469 --> 00:36:42.969 concrete to formal operations because their working 00:36:42.969 --> 00:36:45.630 memory expands, allowing them to hold more abstract 00:36:45.630 --> 00:36:48.170 variables in mind simultaneously. That's the 00:36:48.170 --> 00:36:51.809 idea. And finally, modern cognitive science using 00:36:51.809 --> 00:36:54.829 newer technologies has contradicted some of his 00:36:54.829 --> 00:36:57.989 most famous empirical findings. The most famous 00:36:57.989 --> 00:37:01.230 failure is perhaps his observation of the A -not 00:37:01.230 --> 00:37:03.949 -B error. Let's remind everyone of that. The 00:37:03.949 --> 00:37:06.309 child watches an object hidden repeatedly at 00:37:06.309 --> 00:37:08.909 location A, then watches it moved and hidden 00:37:08.909 --> 00:37:12.010 at location B, but they still search at A. And 00:37:12.010 --> 00:37:14.570 Piaget interpreted this as a lack of fully developed 00:37:14.570 --> 00:37:17.150 object permanence. They can't fully separate 00:37:17.150 --> 00:37:19.769 the object's existence from their previous successful 00:37:19.769 --> 00:37:22.389 action of finding it at A. But modern researchers 00:37:22.389 --> 00:37:25.349 say this isn't a purely cognitive deficit. No. 00:37:25.860 --> 00:37:28.420 Dynamic systems theory in particular offers a 00:37:28.420 --> 00:37:31.119 strong rebuttal. Studies show that babies would 00:37:31.119 --> 00:37:33.980 not make the A, not B error if, for instance, 00:37:34.139 --> 00:37:36.079 they had small weights added to their arms in 00:37:36.079 --> 00:37:38.539 the A phase that were then removed when the object 00:37:38.539 --> 00:37:41.199 was moved to B. It suggests the error is not 00:37:41.199 --> 00:37:43.880 due to a pure cognitive lack, but is influenced 00:37:43.880 --> 00:37:46.579 by multiple dynamic factors, muscle memory, attention, 00:37:46.940 --> 00:37:49.739 stance, and memory trace. Performance, in other 00:37:49.739 --> 00:37:52.099 words, is highly context dependent. Similarly, 00:37:52.199 --> 00:37:55.559 the concept of profound egocentrism in the preoperational 00:37:55.559 --> 00:37:58.239 stage has been revised downwards, suggesting 00:37:58.239 --> 00:38:00.760 children acquire perspective -taking skills much 00:38:00.760 --> 00:38:03.420 earlier. Yes. While the Three Mountains task 00:38:03.420 --> 00:38:06.480 showed difficulty, Later, simpler studies by 00:38:06.480 --> 00:38:08.860 Allison Gottmik and others demonstrated that 00:38:08.860 --> 00:38:11.199 babies as young as 18 months can understand that 00:38:11.199 --> 00:38:13.260 other people have desires different from their 00:38:13.260 --> 00:38:16.000 own. If you offer a child crackers and broccoli 00:38:16.000 --> 00:38:18.840 and the experimenter expresses delight only at 00:38:18.840 --> 00:38:21.380 the broccoli, the child will offer the experimenter 00:38:21.380 --> 00:38:23.679 the broccoli, even though the child prefers the 00:38:23.679 --> 00:38:25.920 crackers. They understand that others have distinct 00:38:25.920 --> 00:38:29.519 mental states and desires. Exactly. And finally, 00:38:29.639 --> 00:38:32.000 his view on the sensory motor stage inability 00:38:32.000 --> 00:38:35.079 to grasp abstract concepts. specifically number 00:38:35.079 --> 00:38:37.960 sense, has been widely contradicted. His views 00:38:37.960 --> 00:38:39.860 led early educators to believe that teaching 00:38:39.860 --> 00:38:42.239 even basic arithmetic to very young children 00:38:42.239 --> 00:38:45.360 was developmentally inappropriate. And yet, modern 00:38:45.360 --> 00:38:47.320 studies show that infants as young as six months 00:38:47.320 --> 00:38:50.380 old and even newborns can perceive and discriminate 00:38:50.380 --> 00:38:53.360 abstract numerical quantities. This fundamentally 00:38:53.360 --> 00:38:55.760 challenges the stage sequence regarding the development 00:38:55.760 --> 00:38:58.239 of abstract thought and shows that the concept 00:38:58.239 --> 00:39:01.679 of number is more innate than constructed through 00:39:01.679 --> 00:39:04.039 years of interaction. Despite all these rigorous 00:39:04.039 --> 00:39:06.699 critiques, which have revised and refined many 00:39:06.699 --> 00:39:09.860 specific details, the expert consensus remains 00:39:09.860 --> 00:39:13.900 clear. Piaget's standing is monumental. Absolutely. 00:39:14.079 --> 00:39:16.159 Though the rigidity of his stages and several 00:39:16.159 --> 00:39:18.619 specific empirical findings have been revised 00:39:18.619 --> 00:39:21.260 or discarded, Piaget is the undisputed founder 00:39:21.260 --> 00:39:23.960 of developmental psychology. He provided the 00:39:23.960 --> 00:39:26.460 unified theoretical framework, the core questions, 00:39:26.639 --> 00:39:29.039 and the enduring concept of the child as an active, 00:39:29.159 --> 00:39:31.780 knowledge -constructing, adapting learner. Every 00:39:31.780 --> 00:39:34.019 subsequent developmental theory, both Piagetian, 00:39:34.099 --> 00:39:36.619 Neopiagetian, or those like Vygotsky who reacted 00:39:36.619 --> 00:39:38.940 against him, must use his work as its starting 00:39:38.940 --> 00:39:41.159 reference point. He gave us the map. What an 00:39:41.159 --> 00:39:43.739 incredible intellectual life, and what a legacy. 00:39:44.329 --> 00:39:47.010 We've journeyed from his early work on mollusks 00:39:47.010 --> 00:39:49.030 and the surprising false memory that sparked 00:39:49.030 --> 00:39:51.230 his interest in the constructed nature of reality 00:39:51.230 --> 00:39:54.110 through the systematic observation of children's 00:39:54.110 --> 00:39:56.929 errors on Binet tests that led to his revolutionary 00:39:56.929 --> 00:39:59.949 stages. We've dissected the powerful tension 00:39:59.949 --> 00:40:02.329 between assimilation and accommodation that drives 00:40:02.329 --> 00:40:05.150 all intellectual growth, acknowledged the critical 00:40:05.150 --> 00:40:07.650 importance of his dynamic clinical method, and 00:40:07.650 --> 00:40:09.889 traced his profound impact on constructivist 00:40:09.889 --> 00:40:12.889 education, moral theory, and even the invention 00:40:12.889 --> 00:40:16.000 of the modern. graphical user interface. His 00:40:16.000 --> 00:40:18.559 constructivist idea that knowledge must be actively 00:40:18.559 --> 00:40:20.739 assimilated by a learner with matured mental 00:40:20.739 --> 00:40:24.349 capacity remains so relevant today. Remember 00:40:24.349 --> 00:40:27.789 that Piaget declared in 1934 that only education 00:40:27.789 --> 00:40:30.389 is capable of saving our societies from possible 00:40:30.389 --> 00:40:32.869 collapse. We can see the power of that idea not 00:40:32.869 --> 00:40:35.369 just in mathematics or reading, but in how individuals 00:40:35.369 --> 00:40:38.230 construct their entire moral architecture, moving 00:40:38.230 --> 00:40:40.769 from constrained, absolute rules enforced by 00:40:40.769 --> 00:40:43.789 authority to autonomous, flexible rules negotiated 00:40:43.789 --> 00:40:46.909 through equal peer exchange. That process of 00:40:46.909 --> 00:40:49.690 self -justification and rational structure is 00:40:49.690 --> 00:40:52.630 the ultimate function of the mature mind. That's 00:40:52.630 --> 00:40:55.630 it. That is a profound thought to end on. So 00:40:55.630 --> 00:40:58.210 if Piaget demonstrated that we must constantly 00:40:58.210 --> 00:41:00.349 reconstruct our knowledge at higher levels as 00:41:00.349 --> 00:41:02.789 we mature, shedding the limitations of earlier, 00:41:02.889 --> 00:41:06.409 more egocentric schemata, what long -held adult 00:41:06.409 --> 00:41:09.090 belief or concept based on a youthful, maybe 00:41:09.090 --> 00:41:12.369 less logical schema might you need to reconstruct 00:41:12.369 --> 00:41:15.269 now that you have a higher order, formal, operational 00:41:15.269 --> 00:41:17.150 understanding of the world? That's something 00:41:17.150 --> 00:41:19.329 to think about long after this deep dive ends. 00:41:19.469 --> 00:41:21.190 We hope you feel a little more well -informed. 00:41:21.639 --> 00:41:23.380 That's all for this deep dive. Join us next time.