Given a vector space V, form its top wedge power. This is one-dimensional. And endomorphism of V induces an endomorphism of the top wedge power. But an endomorphism of a 1-dimensional vector space is a number. This number is the determinant.
This is probably the correct generalization of the volume definition.
Strongly disagree. Wittgenstein clears the way for traditional philosophy topics (ethics, aesthetics, etc.) to be taken seriously.
'Engineer types' may react to ethical discussions by pointing out that you can't define right and wrong, and may then wrongly conclude that they don't exist. But Wittgenstein shows that this is an isolated demand for rigor.
My impression is that income tax is less damaging to investment than than corporate taxes and capital gains taxes, while also being less regressive than a sales tax or VAT.