I'm a veteran tester, and we all think we could write a book on the subject. Fortunately, O'Reilly wrote such a book already ('Beautiful Testing'). So I'll just make one other comment not yet covered:

Not all testing can be automated: I'm thinking of UI testing (or verifying all bells n' whistles are in place). It doesn't take long to check, and it's not even the most critical part of the testing process (functional UAT is, imo); but it's the first and last component of the app the end-user sees.

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He had me until this sentence (although the line that he found the theory interesting enough to refute was a very nice touch).

Electrons, photons, and protons are all merely models to explain in tangible terms what the **** is going on down there, so I become skeptical when these terms are utilized to explain/demonstrate quantum mechanics. We know how to use electricity, buy it, sell it, how to protect our kids from it, yet we really don't know what it is. Two and a half degrees in Chemistry has taught me little that's applicable to the English speaking world, save this: we don't have a clue what's going on at that level of reality, but we're absolutely certain it involoves nothing at all that could be described as little balls orbiting other balls and emitting electrical charges. That's merely a model to make sense of it, and an imitation of life at best.

Something else about Quantum Mechanics/Chemistry: If what anyone says doesn't sound medeival, they're probably thinking too hard and incorrectly. It's gotta sound really strange or it's not QM/C.