Concept
In philosophy and logic, contingency is the status of propositions that are neither true under every possible valuation (i.e. tautologies) nor false under every possible valuation (i.e. contradictions). A contingent proposition is neither necessarily true nor necessarily false. Propositions that are contingent may be so because they contain logical connectives which, along with the truth value of any of its atomic parts, determine the truth value of the proposition. This is to say that the truth value of the proposition is contingent upon the truth values of the sentences which comprise it. Contingent propositions depend on the facts, whereas analytic propositions are true without regard to any facts about which they speak. Along with contingent propositions, there are at least three other classes of propositions, some of which overlap: Tautological propositions, which must be true, no matter what the circumstances are or could be (example: "It is the case that the sky is blue or it is not the case that the sky is blue."). Contradictions which must necessarily be untrue, no matter what the circumstances are or could be (example: "It's raining and it's not raining."). Possible propositions, which are true or could have been true given certain circumstances (examples: x + y = 4 which is true with some values of x and y, but false with others; Or there are only three planets which may be true since we may be talking about a different world which itself could be real or hypothetical. The same is true for There are more than three planets ). Every necessarily true proposition, and every contingent proposition, is also a possible proposition. In medieval Scholasticism contingency regarded not solely the freedom of the Most Holy Trinity not to create the universe, but also the order and concatenation of natural events. In the 16th century Scotism and the European Reformed Scholasticism discovered the John Duns Scotus' idea of synchronic contingency, which was able to remove contradictions between necessity, human freedom and the free will of God to create the world.