Every now and then The Big Bang Theory tells a story from Sheldon's (Jim Parsons) past to explain why he is the way he is (last year it explained why he always knocks three times), but the spin-off prequel Young Sheldon is in even better position to make sense of him, since it can show the origin of a particular peccadillo. Which is exactly what it did in Thursday night's episode by explaining how Sheldon came to be a full-grown Californian man who didn't drive.

Until recently, it was firmly established The Big Bang Theory canon that Sheldon Cooper couldn't drive. It was yet another source of tension between him and his friends that he was reliant on them for transportation. There was a whole episode in Season 2 devoted to him getting his learner's permit after he irritated them all so badly while they were chauffeuring him around that he was forced to try to learn. He failed miserably. It was one of his childlike quirks that he never learned to drive.

Thursday's episode of Young Sheldon, "Poker, Faith, and Eggs," took us back to the moment when Sheldon (Iain Armitage) decided driving wasn't for him. His father (Lance Barber) was in the hospital, and the kids wanted to go visit him against their mother's (Zoe Perry) wishes. So George Jr. (Montana Jordan) "borrowed" their Meemaw's (Annie Potts) car and drove them to the hospital. The thing is, George Jr. was a high school freshman whose only prior experience operating a motor vehicle was driving a tractor at 4-H. So the ride was slow and bumpy and fatal to many mailboxes and garbage cans.

"I've often been asked why I never learned to drive a car," grown-up Sheldon said in voiceover. "This night is your answer."

Iain Armitage, <em>Young Sheldon</em>Iain Armitage, Young Sheldon

The twist, though, is that Sheldon actually did learn to drive. It was revealed last season that Sheldon got his driver's license two years ago while he was on a license-acquiring spree and never told anyone. He barely passed, but he did it. But he still would rather be chauffeured than drive, of course.

Is this discrepancy a mistake on the writers' part? Probably. But maybe it tells us something we didn't think we needed to know, like when is Sheldon's narration taking place? Maybe the narration of Young Sheldon is set before Sheldon got his license and he's looking back on his life sometime around 2013.

Young Sheldon airs Thursdays at 8:30/7:30c on CBS.

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