first principles

You are here


In philosophy, first principles are a set of basic, foundational propositions or assumptions that cannot be deduced from any other proposition or assumption.

In a formal logical system, that is, a set of propositions that are consistent with one another, it is probable that some of the statements can be deduced from one another. For example, in the syllogism, ""All men are mortal; Socrates is a man; Socrates is mortal"" the last claim can be deduced from the former two.

A first principle is one that cannot be deduced from any other. The classic example is that of Euclid's (see Euclid's Elements) geometry; its hundreds of propositions can be deduced from a set of definitionsnew, postulates, and common notions: all three of which constitute ""First Principles"".

Wikipedia contributors, ""First principles,"" Wikipedia, The Free Encyclopedia, (accessed January 31, 2007).