How do we know that Babe Ruth existed?

I am a fan of Sean "Mindscape" Carroll. He's a respected theoretical physicist, who has a chair in Philosophy at Johns Hopkins U. For his Mindscape Podcast he cast his net wide and pokes the expertise of his guest: chemistry, ecology, fashion, immunology, mathematics, medicine, oenology, philosophy, as well as physics. After an hour and a bit, I feel a bit better informed if not actually cleverer. Because clever is not about knowing stuff [Babe Ruth was 53 when he died; the Capital of Hungary is Budapest; Brobdingnagians are Big] it's about being able to process stuff. I know a lot - to wit decades of success in Table Quizzes. But there are limited areas [the chicken genome, Portuguese cats] where I know stuff because I've made it my business, through observation and research, to find things out from first principles. For everything else, I rely on trusted sources: hoping, assuming, trusting that someone else has done the deep digging. Because, for certain sure, we can't reinvent the wheel for everything we are certain sure about.

I bet you're convinced that the Earth is round like a ball, as is the sun, moon and planets. But what is the evidence for this hypothesis? Could you marshal that evidence for a crowd of skeptical fans of Terry Pratchett? I wrote some years ago about being wrong-footed on my belief in evolution. Research biologists, even biochemists, accept the theory of evolution by natural selection as fact. But only 1-in-20 of their serried ranks could articulate the evidence for this belief. But many of those same people are prepared to be rude to, and about, people from Tennessee who reckon nature's wonderful diversity and complex interactions are the creation of The Deity.

In August Carroll was chatting to his friend and colleague Stuart Firestein about how science lurches from blunder to error and drags the participants from ignorance to insight . . . and a well-cited paper, or tenure, or a Prize. At one point, the chat revealed that there is a [conspiracy] theory to the effect that there is no evidence that Babe Ruth even ever existed. This [un]hinges on the observation that there is only one moving image purporting to be Babe Ruth. There are loadsa copies in different contexts but it all boils down to this one movie clip. Given a) He died in 1948, decades after moving images became main-stream, b) His baseball stats are frankly incredible c) He is [therefore] probably the most well known baseball player who ever lived. The Theorists consequently experience a too-good-to-be-true meltdown of cognitive dissonance; which is resolved by concluding (and propagating) that Babe Ruth was a madey-uppy construct. Maybe as a conspiracy by Big Baseball to have an unattainable summit to inspire merely mortal players. Who knows with these crazies, huh? After all, Neil Armstrong and Buzz Aldrin never walked on the moon: the whole thing was staged at a studio in Houston.

Carroll and Firestein conclude that the adult response is not to cry "You're all kookaburra cray-cray" but "You know, it's an interesting question. How do we really know there was a Babe Ruth?" . . . "what do we take seriously? Who do we trust? What evidence do we have? How do we judge it?". Now more than ever we need to have a focused crap-detector when AI-bots can hallucinate, and then publish, plausible sounding facts that jest ain't true.