Freedom and practical reason › The fact of reason

Kant calls consciousness of the fundamental moral law a fact of reason. The expression can mislead if "fact" is understood as an observation made by a psychologist. He expressly distinguishes it from an empirical fact. Its claim is that pure reason presents the law as binding without deriving it from an antecedent awareness of freedom.

This is a point about the order of justification. Kant does not begin by observing a free will and then deriving a moral law from what it does. He begins from consciousness of an unconditional requirement and asks what that requirement shows about practical agency.

The claim is stronger than saying that people feel guilty or that societies teach moral rules. A person could experience guilt for a mistaken reason, while a social command might be unjust. The fact of reason concerns the authority Kant attributes to reason's lawgiving, not a guarantee that every experienced demand expresses that law correctly.

A reader can reasonably question this starting point. Why accept that awareness of duty has the authority Kant gives it? The label "fact of reason" does not remove that philosophical question. It identifies what his argument treats as fundamental and helps distinguish his account from an empirical explanation of how moral beliefs arise.