0 the process of making judgments about something based on sensible thinking or logic (= a formal scientific method of thinking about ideas): --
Aquinas takes a rather dim view of discursive reason or ratiocination as compared to sheer understanding.
The detective in the story is known for his gifts of observation and ratiocination.
We can complete it step by step however long the road is and it can't be completed however short the road is if you don't even mark your footprint.
Можем да го завършим стъпка по стъпка, колкото и дълъг да е пътят и не може да бъде завършен, колкото и кратък да е пътят, ако дори не маркирате отпечатъка си.