>Ok thanks. Yeah, 100% guarantee is only valid for death and taxes.
As a scientist (OK, someone who likes to read a little, now and then, about science), I would add "entropy" to the list. In simple terms, this concept simply means that there are certain irreversible processes in nature - especially those that involve energy.
The fact that "entropy increases" (roughly, what increases is unavailable energy), is unavoidable, and can't be un-done, as far as modern science knows.
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The basic problem with the protection against decompilation, of course, is that the executable, no matter how it is encrypted, has to be somehow decrypted - even if it be only briefly - in order to execute.
Difference in opinions hath cost many millions of lives: for instance, whether flesh be bread, or bread be flesh; whether whistling be a vice or a virtue; whether it be better to kiss a post, or throw it into the fire... (from Gulliver's Travels)