Philosophy
Deontological Ethics and the Categorical Imperative
Quick fact
Kant argued that lying is always wrong, even to a murderer at the door asking for your friend's hiding place—because a universal law of lying would destroy trust and make promises meaningless.
Why this is interesting
You're about to hear 'it's your duty'—but what makes something a duty? Immanuel Kant's answer might surprise you: not results, not feelings, but pure reason itself.