If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
Notes for future OT posters:
1. Please add the 'open_thread' tag.
2. Check if there is an active Open Thread before posting a new one. (Immediately before; refresh the list-of-threads page before posting.)
3. Open Threads should be posted in Discussion, and not Main.
4. Open Threads should start on Monday, and end on Sunday.
Well, it's hard to articulate. There's of course nothing wrong with assumptions per se, since axioms indeed are assumptions, my peeve is with the baggage that comes with it. People say things like "what if the assumptions are wrong?", or "I don't think that axiom is clearly true", or "In the end you can't prove that your axioms are true".
These questions would be legitimate if the goal were physical truth, or a self-justifying absolute system of knowledge or whatever, but in the context of mathematics, we're not so interested in the content of the assumptions as we are in the structure we can get out of them.
In my experience, this kind of thing happens most often when philosophically inclined people talk about things like the Peano axioms, where it's possible to think we're discussing some ideal entity that exists independently of thought, and disappears when people are exposed to, say, the vector space axioms, or some set of axioms of set theory, where it becomes clear that axioms aren't descriptions but definitions.
Actually, you can ignore everything I've said above, I've figured out precisely what I have a problem with. It's the popular conception of axioms as descriptive rather than prescriptive. Which, I suppose OP was also talking about when they mentioned building blocks as opposed to assumptions.
That's a valid question in a slightly different formulation: "what if we pick a different set of assumptions?"
But that, on the other hand, is pretty stupid.
Well, normally you want your axioms to be descriptive. If you're interested in reality, you would really prefer your assumptions/axioms to match reality in some useful way.... (read more)