A few different theories of what the "truth" means have been touched on above. Theories include: 1. Coherence theory Statements or judgments are only true if they cohere with other accepted truths. Logical deduction feeds into this idea. Note that facts are largely irrelevant to this theory, so a statement like "All men are tidal waves" can generate a coherent set of "truths". 2. Correspondence theory Statements or judgments are true if they correspond to the facts of experience. Under this view, truth must connect with the "real world". So, a statement like "All men are mortal" is true in a way that "All men are tidal waves" is not. 3. Pragmatic theory Under this point of view, "truth" is whatever works effectively for each individual in his/her life. Under this view, different people can have different "truths". Whatever floats their boat is true, so to speak. So, if it is useful to you to think of all men as tidal waves, then that's just fine for you. 4. Performative theory This theory holds that when somebody says "That's true", they are not saying anything about the facts or the world at all, but they are merely saying something similar to "I endorse/agree with that position." Under this view, saying "All men are tidal waves" is not to make any statement apart from "I think/agree that all men are tidal waves."