Introduction: Things change: objects come into existence, last for a while, go out of existence, move through space, change their parts, change their qualities, change in their relations to things. All this would seem to be uncontroversial. But philosophical attention to any of these phenomena can generate perplexity and has resulted in a number of long-standing puzzles. One of the most famous puzzles about change threatens to demonstrate that nothing can persist through time, that all existence is momentary at best. Let’s use the term ‘alteration’ for the sort of change that occurs when a persisting object changes its properties.
Comment: A good overview of the philosophical issues involved in persistence through time. Would be a good preliminary material in a philosophy of time course. Or, since this is a fundamental philosophical problem, could be used in an introduction to philosophy course as a more clear alternative or supplement to ancient sources.