On: The 2,500 year old history of why Python’s all([]) returns True

[thaumasiotes]

De Morgan's law isn't the right one for this. You want the identity ∀x.P(x) ⟺ ¬∃x.¬P(x).

∀x.P(x) is obviously true when the universe is empty -- no counterexamples exist. ∃x.P(x) is obviously not true in that case -- no examples exist.

[maweki → thaumasiotes]

That is De Morgan if you expand the quantifiers.

[thaumasiotes → maweki]

You have to make some assumptions if you want to "expand the quantifiers". In particular, you have to assume that the universe is non-empty, which is a really bad idea if you're commenting in this thread.