Invariance as a basis for necessity and laws

Abstract Many philosophers are baffled by necessity. Humeans, in particular, deeply disturbed the idea of necessary laws nature. In this paper I offer a systematic yet down to earth explanation necessity and terms invariance. The type invariance employ for purpose generalizes an used meta-logic. main is that properties relations general have certain degrees invariance, some properties/relations stronger degree than others. highly-invariant associated with high governing/describing these properties, explains such both logic science. This non-mysterious has rich ramifications fields, including formality mathematics, apparent conflict between contingency science its laws, difference logical-mathematical, physical, biological laws/principles, abstract character applicability mathematics science, scientific realism, logical-mathematical realism.