Published online by Cambridge University Press: 31 January 2023
Some of what is true about the world is thought, by some, to be true of necessity. Other truths about the world are merely contingently true, it is said. Next we get a familiar distinguishing of necessity into its various kinds. Anything whose contrary would contradict the laws of logic is logically necessary. Anything compatible with these laws is logically contingent. There are, of course, grave problems in finding a principled way of discriminating the logical truths from all the others. Some propositions are not logically necessary but are metaphysically necessary. For Kant, I suppose, the alleged facts that every event had a cause, and that in any change a substance remained unchanged would be such facts. So, I suppose, would be the necessary but synthetic truths of geometry and arithmetic. For more contemporary philosophers genuine identity statements, either singular or general, might have such a status.