That's a really hard belief to justify. And what implications would that position have? Should biologists give up?

Biologists don't try to reason everything from first principles.

Actually, neither do Rationalists, but instead they cosplay at being rational.

> Biologists don't try to reason everything from first principles.

What do you mean? The biologists I've had the privilege of working with absolutely do try to. Obviously some work at a higher level of abstraction than others, but I've not met any who apply any magical thinking to the actual biological investigation. In particular (at least in my milieu), I have found that the typical biologist is more likely to consider quantum effects than the typical physicist. On the other hand (again, from my limited experience), biologists do tend to have some magical thinking about how statistics (and particularly hypothesis testing) works, but no one is perfect.

Setting up reasoning from first principles vs magical thinking is a false dichotomy and an implicit swipe.

Ok, mea culpa. So what distinction did you have in mind?

Reasoning is one information-processing process, performed by humans, with bounds on what it can accomplish. It works in a limited context and is inherently incomplete and imperfect. Other non-logical processes, emergent processes, parallel processes such as evolution, process information in ways reasoning cannot. It perhaps should not be surprising that we may have internal systems of understanding that follow these principles, instead of only those of logic or reasoning.

Reasoning from first principles cannot span very far in reality, as for starters the complexity of the argument quickly overwhelms our capacity for it. Its numerous other limits have been well-documented.

Logicomix, Gödel Escher Bach are some common entry points.

>Gödel Escher Bach

I'm kinda new here but am surprised I haven't seen this book mentioned more. Maybe I just haven't seen it or it's old news but it seems right up HNs alley.

It would imply that when dealing with complex systems, models and conceptual frameworks are, at the very best, useful approximations. It would also imply that it is foolhardy to ignore phenomena simply because they are not comprehensible within your preferred framework. It does not imply biologists should give up.

How reducible is the question. If some particular events require a minimum amount of complexity, how to do you reduce it below that?

I think that chemistry, physics, and mathematics, are engaged in a program of understanding their subject in terms of the sort of first principles that Descartes was after. Reduction of the subject to a set of simpler thoughts that are outside of it.

Biologists stand out because they have already given up on that idea. They may still seek to simplify complex things by refining principles of some kind, but it's a "whatever stories work best" approach. More Feyerabend, less Popper. Instead of axioms they have these patterns that one notices after failing to find axioms for a while.

On the other hand, bio is the branch of science with a single accepted "theory of everything": evolution.

Evolution is a theory of the origin of species via natural selection of heritable traits; evolution is not a theory of biogenesis, the origin of life itself.

That's a fine counterexample to "theory of everything", and fertile ground for spirited debate. But I think it's a distinction thats relevant to <1% of the work that biologists do, so like... does it matter?

Yeah, I almost wrote ‘nearly have a theory of everything’ for that reason, but decided it wasn’t worth the extra words. We have a few plausible outlines of how life started, and IMO it doesn’t really matter all that much which one(s) actually happened. When we ourselves are doing biogenesis, there’s no requirement that it has to happen the way it happened before. It would be interesting to know, though, so if in your estimation we don’t have a theory of everything because of that, I’m okay with that.

Several different definitions are being bandied about. If you think of reduction as understanding a material system in terms of its components, biology is now reductionist, having abandoned vitalism.

Concretely we know that there exist irreducible structures, at least in mathematics: https://en.wikipedia.org/wiki/Classification_of_finite_simpl...

The largest of the finite simple groups (themselves objects of study as a means of classifying other, finite but non-simple groups, which can always be broken down into simple groups) is the Monster Group -- it has order 808017424794512875886459904961710757005754368000000000, and cannot be reduced to simpler "factors". It has a whole bunch of very interesting properties which thus can only be understood by analyzing the whole object in itself.

Now whether this applies to biology, I doubt, but it's good to know that limits do exist, even if we don't know exactly where they'll show up in practice.

That's not really true, otherwise every paper about it would be that many words long. The monster group can be "reduced" into its definition and its properties which can only be considered a few at a time. A person has a working memory of three to seven items.