Ratiocination (noun)

The process of logical and methodical reasoning; the use of clear, sound reasoning in order to arrive at a conclusion.

Origin:

From the latin ratio (reason) and -cination (process of), from cinare (to sift).

Examples:

1. The detective's ratiocination led him to solve the crime.
2. The lawyer's ratiocination was key in winning the case.
3. His ratiocination was impressive and he was able to deduce the solution to the problem.
4. The philosopher's ratiocination was deep and complex.
5. The scientist's ratiocination led to the discovery of a new theory.