logic

n. 1 a science of reasoning. B particular system or method of reasoning. 2 a chain of reasoning (regarded as sound or unsound). B use of or ability in argument. 3 inexorable force, compulsion, or consequence (the logic of events). 4 a principles used in designing a computer etc. B circuits using this.  logician n. [related to *-logic]

n. The science or art of exact reasoning, or of pure and formal thought, or of the laws according to which the processes of pure thinking should be conducted; the science of the formation and application of general notions; the science of generalization, judgment, classification, reasoning, and systematic arrangement; correct reasoning.