| >I say they're equivalent because it is possible to losslessly convert one to the other by wasting massive amounts of disk space and time. There is a classical algorithm for every quantum algorithm if you're willing to waste a massive amount of space and time. There is a finite-state automata that can recognize any string some Turing machine can recognize. Yet we recognize these as distinct classes of computation. Mathematicians can get away with ignoring the tractability of finding an object with such and such properties. The rest of us can't. Sure, there is a formal equivalence between LLMs and Markov chains, and this formal equivalence is useful for analysis. But this equivalence is not a constraint on the nature of the computations LLMs are doing. The formal equivalence does not mean that LLMs are "just predicting the next token". A probability distribution is a formal characterization of the statistical relationships between inputs and outputs. But this formalization does not undermine potentially further structure underlying the probability distribution (e.g. a deterministic mapping from inputs to outputs). >if the transformer is reasoning, so is the hash map built from it. Definitely not. "Formal" reasoning is making deductions based on the "form" or shape of some statement. In other words, transitioning from some token sequence to another sequence in virtue of the semantic structure of the token sequence (as opposed to its semantic content). Thus a necessary condition for reasoning is the ability to inspect the structure of the input rather than see it as a formless blob. Transformers can plausibly do this; lookup tables, Markov chains, etc necessarily cannot. >For the record, "X is more expressive than Y" means "there exists at least one thing that Y cannot represent and X can". Maybe expressive is the wrong word. But when a model has to wait for someone else to do the work then copy the answer, I call bullshit on it being (computationally) equivalent. |
Remember, if the mapping from input to output is identical, there exists no test operating on the machines' output that can differentiate them. You can't tell from "conversing with" a machine whether it is or is not doing what you say around "inspecting" the input.