Reflections on AI at the End of 2025

* For years, despite functional evidence and scientific hints accumulating, certain AI researchers continued to claim LLMs were stochastic parrots: probabilistic machines that would: 1. NOT have any representation about the meaning of the prompt. 2. NOT have any representation about what they were going to say. In 2025 finally almost everybody stopped saying so.

* Chain of thought is now a fundamental way to improve LLM output. But, what is CoT? Why it improves output? I believe it is two things: 1. Sampling in the model representations (that is, a form of internal search). After information and concepts relevant to the prompt topic is in the context window, the model can better reply. 2. But if you mix this to reinforcement learning, the model also learns to put one token after the other (each token will change the model state) in order to converge to some useful reply.

* The idea that scaling is limited to the number of tokens we have, is no longer true, because of reinforcement learning with verifiable rewards. We are still not at AlphaGo move 37 moment, but is this really impossible in the future? There are certain tasks, like improving a given program for speed, for instance, where in theory the model can continue to make progress with a very clear reward signal for a very long time. I believe improvements to RL applied to LLMs will be the next big thing in AI.

* Programmers resistance to AI assisted programming has lowered considerably. Even if LLMs make mistakes, the ability of LLMs to deliver useful code and hints improved to the point most skeptics started to use LLMs anyway: now the return on the investment is acceptable for many more folks. The programming world is still split among who uses LLMs as colleagues (for instance, all my interaction is via the web interface of Gemini, Claude, …), and who uses LLMs as independent coding agents.

* A few well known AI scientists believe that what happened with Transformers can happen again, and better, following different paths, and started to create teams, companies to investigate alternatives to Transformers and models with explicit symbolic representations or world models. I believe that LLMs are differentiable machine trained on a space able to approximate discrete reasoning steps, and it is not impossible they get us to AGI even without fundamentally new paradigms appearing. It is likely that AGI can be reached independently with many radically different architectures.

* There is who says chain of thought changed LLMs nature fundamentally, and this is why they, in the past, claimed LLMs were very limited, and now are changing their mind. They say, because of CoT, LLMs are now a different thing. They are lying. It is still the same architecture with the same next token target, and the CoT is created exactly like that, token after token.

* The ARC test today looks a lot less insurmountable than initially thought: there are small models optimized for the task at hand that perform decently well on ARC-AGI-1, and very large LLMs with extensive CoT achieving impressive results on ARC-AGI-2 with an architecture that, according to many folks, would not deliver such results. ARC, in some way, transitioned from being the anti-LLM test to a validation of LLMs.

* The fundamental challenge in AI for the next 20 years is avoiding extinction.