The limitations of Large Language Models in achieving true Artificial General Intelligence (AGI) hinges on their inability to generate genuinely novel scientific discoveries, according to Columbia CS Professor Vishal Misra. “Any LLM that was trained on pre-1915 physics would never have come up with the theory of relativity. Einstein had to sort of reject the Newtonian physics and come up with this space time continuum. He completely rewrote the rules."
Misra spoke with Martin Casado and Erik Torenberg at a16z about the inherent constraints of LLMs, the reasons behind the effectiveness of chain-of-thought reasoning, and a vision for what genuine AGI would entail.
Misra argues that LLMs, at their core, are sophisticated pattern-matching machines that excel at predicting the next token in a sequence based on vast amounts of training data. This process, while impressive, fundamentally differs from human reasoning, which involves creativity, intuition, and the ability to challenge existing paradigms. "AGI will be when we are able to create new science, new results, new math. When an AGI comes up with a theory of relativity, it has to go beyond what it has been trained on to come up with new paradigms, new science. That's my definition of AGI."
A key insight from the discussion is that LLMs operate within a "Bayesian manifold," essentially navigating a pre-defined space of possibilities shaped by their training data. While they can refine their predictions and improve their accuracy within this space, they lack the capacity to transcend it and create entirely new concepts or theories.
Chain-of-thought reasoning, a technique that involves prompting LLMs to break down complex problems into a series of smaller, more manageable steps, works because it reduces the entropy, or uncertainty, at each stage of the process. "Chain-of-thought reasoning and entropy reduction" are inherently linked. By guiding the LLM through a structured sequence of steps, the prompt engineer effectively narrows down the range of possible outputs, leading to more coherent and accurate results. However, this technique does not enable the LLM to generate truly novel insights.
