Logic as an art is the clever manipulation of data to arrive at a desired or foregone conclusion through reasoning. This is used extensively and effectively by lawyers and those who try to prove the existence of God.
Logic as a science is used: (a) In the theoretical framework of science to deduce observed and observable effects from the hypotheses at the start of a theory. (b) In mathematics for deriving theorems and important result, and for justifying procedures: as in the field of Analysis in Calculus.
Spurts of Thought 