My dog Stewart...

...has a torn ACL. Or at least that's what his vet tells us. Actually, two veterinarians: our old one in Glenview and our new one in the city. But my wife and I are skeptical; he seems to move just fine except at night when he's a little stiff. Is it really a torn ACL, or is it merely hip dysplasia or early onset arthritis? Now I'm not an expert in these things, but just the other day, for example, Stewart gave spirited chase to a squirrel in the park. Could a human with a torn ACL do something like that? I doubt it.

But, as I said, I'm not a veterinarian and don't feel like going back to school for years and years just to find the answer. So if vets keep telling us that Stew has a torn ACL, then at some point we'll seriously consider surgery.

On a similar note, my old beater convertible wouldn't start one day last month and an auto mechanic told me I needed a new starter. I didn't feel like asking around so I just told him to go ahead and fix it. If I had shopped, though, and eight or nine out of ten auto mechanics told me the same thing I'd probably conclude that that was the problem.

Would either of these two examples be airtight? No; in fact, our current vet told me they have been convinced on more than one occasion that a dog had a torn ACL only to find out otherwise when he went under the knife.

Where am I going with all this? Yesterday, I wrote a post about climate change and -- like Marco Rubio -- conceded that I'm not a scientist, man. But, unlike the junior senator from Florida, I respect the scientific method and defer to the consensus among scientists that not only is climate change real but is to some extent man-made. And, if I really doubt it, it's up to me to either produce some evidence to the contrary or concede the point.

End of story? Not exactly. Just to confuse the issue a little, I remember when everyone -- and I mean everyone -- was convinced that Saddam Hussein had weapons of mass destruction. Everyone except me. (It just didn't pass the smell test.) So I was right. Once. Even though American, British, German and every other intelligence agency in the world thought he did. But if you had to bet on whether or not Iraq had WMD, would you have bet with them, or me? Exactly.

So, until experts -- be they veterinarians, auto mechanics, intelligence agents or climate scientists -- are proven wrong, it's probably best to honor their expertise and listen to them.

P. S. I'll let you know how that whole ACL thing turns out.