[GuidoHunter]

Actually, yes, matter can be destroyed, but not by any means already proposed.

The Law of Conservation of Matter states that matter can neither be created nor destroyed by ordinary chemical means. Jewpin's example with the wood illustrates conversion of matter by ordinary means (wood turning into ash and smoke). His black hole example was a bit off, though. Black holes aren't actually voids. They're just extremely dense balls of a whole lot of matter. So when something gets sucked into a black hole, it just adds to the amount of matter and makes the gravitational force greater.

The only way to actually destroy matter is by introducing it to its respective antimatter. They annihilate each other completely. Of course, you could take the idea that matter and energy are equivalent and run with it by saying that the matter was just converted into energy, but for the purposes of this argument, observable matter is no more when it encounters antimatter and is effectively destroyed.

--Guido

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