I won’t try to summarize Korman’s post but will quote a snippet to entice you to read it in full:
Santa Claus is as real as I am.
Santa is, in truth, more real than I am. He has a bigger effect on the world.
After all, how many people know Santa Claus? If I walk down Market Street in San Francisco, there’s a good chance that a few people will recognize me; I happen to be a distinctive-looking guy. There’s a chance that one or two of those people will even know my name and a few things about me, but the odds are greatly against it. But if Santa takes the same walk, everybody (or nearly everybody) will recognize him, know his name, know a number of things about him, even have personal stories about him. So who is more real?