I fully accept that there's tons of overlap, otherwise why would it matter that he is a Ph.D. mechanical engineer. It's not like I think he's got a Ph.D. in English lit. or something.
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You could call him Dr. Oz because there was no ambiguity.
Again, Dr. Phil and Dr. Oz have established those names as their veritable trademarks. There's just no ambiguity. The "Dr." part doesn't mean anything about their expertise or authority, more than it means, the celebrity himself. His person. Not that he's a doctor of anything, that's just why he's justified in calling himself "Dr.", ofc, along with D.O.s and D.M.D.s and Th.D.s and all the other diplomas with a D on it–J.D. even, a lawyer, a juris doctor, is also justified in calling himself "Dr.", technically.
Philosophy is the study of ethics, metaphysics, and epistemology.
It's not an insult. "Doc Brown" reminds me of Back to the Future, I never have that problem with Dr. Phil or Dr. Oz, because there's no ambiguity. Like "Dr. Mike" is ambiguous since there are so many.
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Correct. He's a doctor of the philosophy of mechanical engineering. Would be nice if we had some doctors of the philosophy of geology weighing in on H.P.T., no? But we don't have any. The one geology Ph.D. candidate I saw eviscerated H.P.T. because of something they all call the "heat problem" which is that the amount of sedimentary rock allegedly formed due to the Flood under Hydro-plate theory would release too much heat too quickly, it would kill everything. So that's the biggest defeater against it. H.P.T. does have an answer to the heat problem, but the initial plausibility of that answer being a "just-so" explanation seems non-negligible. But this is why it would be nice to see what Ph.D. geologists think, since we're just wanting to get a second opinion on Dr. Brown's H.P.T.
Whoops, I mean Mr. Brown.
No, he didn't. We just must remember that there is such a thing as a second opinion, even with authentic medical doctors giving medical opinions. This is geology, I want to see some second opinions from Ph.D. geologists, would be nice anyway, no?