Thomistic ethics defines the first principle of practical reason as "good is to be done and pursued, and evil is to be avoided.
"[1] For Kant, practical reason has a law-abiding quality because the categorical imperative is understood to be binding one to one's duty rather than subjective preferences.
Since Descartes practical judgment and reasoning have been treated with less respect because of the demand for greater certainty and an infallible method to justify beliefs.
It has often been disputed in philosophy whether practical reasoning is purely instrumental or whether it needs to be based on values.
[3][4][5] The following argumentation scheme for value-based practical reasoning is given in Atkinson, Bench-Capon & McBurney (2005, pp. 2–3).