BI 181 Max Bennett: A Brief History of Intelligence
Dec 25, 2023
auto_awesome
Max Bennett, an entrepreneur and author, discusses the breakthroughs in brain evolution and their impact on intelligence. Topics covered include the role of the neocortex in simulating and imagining, counterfactual learning, episodic memory, and the challenges of building human-like AI systems.
The first breakthrough in brain evolution involves the emergence of steering and navigation, allowing efficient trade-off decision making based on sensory input.
The second breakthrough is the development of reinforcement learning, enabling animals to learn arbitrary behaviors through trial and error and optimize behavior based on reward signals.
The third breakthrough is the development of simulating abilities in mammals through the evolution of the neocortex, allowing for vicarious trial and error, counterfactual learning, and episodic memory.
Deep dives
Steering and taxis navigation
The first breakthrough in brain evolution involves the emergence of steering, or taxis navigation. This is the development of centralized brains that enable animals to make clear trade-offs and navigate the environment based on sensory input. For example, nematodes use a clever algorithm where sensors for increasing good things drive forward momentum, while sensors for decreasing good things or increasing bad things drive turning. This breakthrough allows for efficient navigation and trade-off decision making.
Reinforcement learning in vertebrate brains
The second breakthrough is the emergence of reinforcement learning, especially in vertebrate brains. This type of learning allows animals to learn arbitrary behaviors through trial and error. This breakthrough is evident in the presence of temporal difference learning, a type of reinforcement learning, demonstrated in vertebrate brains. This type of learning is crucial for adapting to the environment and optimizing behavior based on reward signals.
Simulating and the emergence of mammals
The third breakthrough is the development of simulating abilities in mammals. Simulating involves the ability to imagine or simulate different states of the world, including possible futures, counterfactual scenarios, and episodic-like memories. This breakthrough is associated with the evolution of the neocortex, a brain structure found in mammals. Through simulating, mammals gain new abilities such as vicarious trial and error, the capacity for counterfactual learning, and episodic memory. These abilities are made possible through the neocortex's ability to simulate different mental states.
Mentalizing and primate brains
The fourth breakthrough is mentalizing, which refers to the development of the ability to model one's own thinking and the minds of others. This breakthrough is associated with the emergence of granular prefrontal cortex and sensory cortex in primate brains. Mentalizing enables primates to have theory of mind, or the ability to understand and infer the mental states of others. It also facilitates imitation learning and the anticipation of future needs, allowing individuals to plan and make choices based on imagined future states. These abilities contribute to the complexity of primate cognition and social behavior.
The Power of Language and Idea Evolution
Language allows for the transfer of ideas between brains, enabling vicarious learning and the evolution of ideas or memes. This process has led to an explosion of complexity and the development of culture. With the advent of artificial intelligence (AI), the economic incentive is to build AI systems that align with human preferences and abilities. However, they will also possess abilities that humans don't have, such as immortality and lack of evolutionary baggage. The future of humans and AI can take one of three paths: subduing AI through regulation, humans being supplanted by AI, or a merging of humans and AI systems. The latter is technologically challenging due to the difficulty of translating biological signals to AI systems, making it less likely than the others.
Avoiding Functional Assignments and Focusing on Algorithmic Understanding
Instead of assigning clean functions to brain structures, it is more fruitful to focus on understanding the algorithms implemented by structures. The evolutionary story offers a useful tool to avoid decomposition and reverse engineering of the brain. The goal is to determine what new abilities emerge when a neocortex is added to the existing complex network. AI can play a pivotal role in this process by approximating different structure algorithms and simulating the emergent properties of a whole brain model. By doing so, a better understanding of the brain can be achieved.
Three lines of research formed the basis for how Max synthesized knowledge into the ideas in his current book: findings from comparative psychology (comparing brains and minds of different species), evolutionary neuroscience (how brains have evolved), and artificial intelligence, especially the algorithms developed to carry out functions. We go through I think all five of the breakthroughs in some capacity. A recurring theme is that each breakthrough may explain multiple new abilities. For example, the evolution of the neocortex may have endowed early mammals with the ability to simulate or imagine what isn't immediately present, and this ability might further explain mammals' capacity to engage in vicarious trial and error (imagining possible actions before trying them out), the capacity to engage in counterfactual learning (what would have happened if things went differently than they did), and the capacity for episodic memory and imagination.
The book is filled with unifying accounts like that, and it makes for a great read. Strap in, because Max gives a sort of masterclass about many of the ideas in his book.
0:00 - Intro
5:26 - Why evolution is important
7:22 - Maclean's triune brain
14:59 - Breakthrough 1: Steering
29:06 - Fish intelligence
40:38 - Breakthrough 3: Mentalizing
52:44 - How could we improve the human brain?
1:00:44 - What is intelligence?
1:13:50 - Breakthrough 5: Speaking
Remember Everything You Learn from Podcasts
Save insights instantly, chat with episodes, and build lasting knowledge - all powered by AI.
