<Dl> <Dd> 7006100000000000000 ♠ 1,000,000 grains of sand is a heap of sand (Premise 1) </Dd> <Dd> A heap of sand minus one grain is still a heap . (Premise 2) </Dd> </Dl> <Dd> 7006100000000000000 ♠ 1,000,000 grains of sand is a heap of sand (Premise 1) </Dd> <Dd> A heap of sand minus one grain is still a heap . (Premise 2) </Dd> <P> Repeated applications of Premise 2 (each time starting with one fewer grain) eventually forces one to accept the conclusion that a heap may be composed of just one grain of sand .). Read (1995) observes that "the argument is itself a heap, or sorites, of steps of modus ponens": </P>

When do many grains of sand become a pile of sand