Akrasia
Etymology
From ancient Greek akrasia, "lack of command" or "lack of self-control," from a-, "without," and kratos, "power, command." Socrates, as reported by Plato, doubted it could truly exist — he held that no one knowingly does wrong, so apparent akrasia is really ignorance — while Aristotle, in the Nicomachean Ethics, accepted it as real and tried to explain how appetite can override reason in the moment.
noun · /uh-KRAY-zee-uh/
The state of acting against your own considered better judgment — knowing the wiser course and taking the other one anyway.
What it names
The everyday gap between knowing and doing — the scroll instead of the sleep, the cigarette after the resolution — that mere information never seems to close.
Example
He knew every argument for saving more and still didn’t; it was pure akrasia, not ignorance.
Related idea
Hyperbolic discounting offers a modern economic account of why akrasia happens; akrasia is the older, broader name for the failure itself.