I wrote the book on black fatherhood. Literally.

“Becoming Dad: Black Men and the Journey to Fatherhood” was a deep dive into the absence and uninvolvement of African-American fathers in the lives of their children. Like many observers, I inferred that absence and uninvolvement from statistics showing a decline in marriage among African Americans so that the average black baby was now born to an unwed couple.

For years, I’ve used that book as a defense when white people taunted me that the dysfunction so often afflicting black kids has nothing to do with racism and everything to do with the failure of their fathers. It was my way of proving that not only did I comprehend those failures, but I was unafraid to call my own folks to account.

Not that white people are the only ones who perceive African-American men as bad dads. The book opens with me explaining to my friend Roy that I’m writing about black men and fatherhood, whereupon he laughs and asks, “What does the one have to do with the other?” Roy was black, a father of two.

And he was wrong. Those white people were wrong. I was wrong, too.

First, we have to take a trip to Morehouse College, from which a viral image emerged. It shows Nathan Alexander, a mathematics professor, giving a lecture with a 5-month-old baby strapped to his chest.

She was the daughter of one of his students, a 26-year-old senior named Wayne Hayer. Hayer, who works two jobs and is studying kinesiology, had taken the baby so his wife would not have to struggle with her on public transit while running an errand. When he couldn’t find child care, he decided to bring her to class with him, taking Alexander up on a previous offer to do so if he ever needed to.

Not only did Alexander welcome the baby to class, but when he saw Hayer was unable to take notes while caring for her, he offered to hold her. The resulting image, taken by another student, has been retweeted almost 80,000 times. Alexander has been deservedly praised for going above and beyond to support his student. But it is the young family man who is our focus here.

You’d be hard-pressed to find more eloquent refutation of the lie of the absent and uninvolved black father than this young man with his two jobs, taking his baby to class. Some people will think him exceptional. He isn’t.

We have a 2013 study from the Centers for Disease Control and Prevention to thank for correcting us on this. Yes, black fathers are less likely to be married. But — and this holds whether they live with their children or not — it turns out from this survey of more than 10,000 men that they are also more likely than white or Hispanic dads to eat with their children, to dress their children, to help their children go potty, to play with their children, to read to their children, to be, in a word, involved.

So Hayer is no exception; he’s the norm. He’s what my pastor likes to call a “James Evans type of dad” after the father on “Good Times” who would do whatever, whenever, make a way by any means necessary, in order to secure his family. There are a lot of black men like that, something for which they often get no credit, not only from white people but also from black ones.

We’d all do well to ponder why that is, why the lie was so easy to believe.

The little one, we are told, was well behaved in math class, eventually falling asleep. Apparently, she felt secure. And why not? After all, she had Mr. Alexander’s support.

And her father was right there.