These are the answers by mathematician Maxim Hendriks to the ten questions about intuitionism:
No.
No.
No.
Mu.
I do not like the metaphysical implications of the words "meaningful" and "true" here.
Mu.
I do not like the metaphysical implications of the words "meaningful" and "true" here.
No.
Mu.
This depends on the context, specifically on what mean by the word "implication". Within the calculus of propositional logic, I would answer "yes". Within constructive logic, "no". And within the context of everyday language "no" as well, because implication has a causal meaning in that setting (causality being a primitive notion of the model of the world a speaker has at a given moment).
No.
(A very definite "no".) One gains information by a constructive proof. But one also gains a lot of information from a non-constructive proof, albeit different information.
Yes.
When doing mathematics per se, different methods give different (interesting) results. When applying mathematics to real-world problems, some methods might be useless at a given moment, although theoretically very interesting.
No.
The concept of "truth" is very expedient, but when thinking about the connection between thought and the world, we might prefer to work without it, since it presupposes a "picture view" of what perceiving is, and thereby a metaphysical structure of the world. Is that structure present?
Maybe we better take a pragmatist view, cf. Richard Rorty, "Objectivism, relativism and truth".