From the Time interview with JK Rowling:
"As I look back over the five published books," she says, "I realize that it's kind of a litany of bad fathers. That's where evil seems to flourish, in places where people didn't get good fathering."
According to Rowling, evil seems to flourish in places where people didn't get good fathering. That's quite a statement; is it one that most people agree with?
And which "bad fathers" was JKR referring to, anyway?
Voldemort's father, of course, is one of the obvious examples. HBP actually paints Tom Riddle, Sr. in a much better light than previously, now that we know he was trapped by a love potion, but there's still no excuse for abandoning a son.
Mr. Dursley is another. He abuses Dudley through smothering and indulgence, and as a father-figure of a sort to Harry, he fails miserably as well, treating him to neglect and emotional abuse. Still, he's not Harry's father; it's only Dudley whose character seems to have been negatively affected.
Snape's father is another, though he doesn't get nearly as much discussion. Prior to the release of HBP, the fandom as a whole assumed that Snape was a Pureblood, or at least that he had no recent Muggle ancestors. After all, Snape had become a Deatheater, seemed to believe that wizards were inherently better than Muggles.
Now we know better. Snape's father was an actual Muggle - not just a Muggle-born, but a Muggle. Hermione compares him to Voldemort, and suggests that he, like Voldemort, was ashamed of his parentage and thus grew to hate Muggles.
In this light, the scene in Snape's Penseive, of his mother cowering before his father, becomes even more significant. Apparently, his father was not exactly a wonderful person - and no doubt Snape believed that all Muggles are like this. It's quite possible that the situation was somewhere between Seamus's and Voldemort's: when Eileen told Tobias that she was a witch, he didn't leave her, but he resented her and possibly even began to hate her. And if he didn't leave her because she was already pregent with Severus, that might very well have caused him to resent his son, causing Severus even worse views of Muggles.
The only other bad dad in the Harry Potter books that occurs to me at the moment is Crouch, Sr. who seems to have been at least largely at fault for his son's going astray.
Can anyone think of any others? "Litany of bad fathers" makes it seem like there are quite a lot of them.... Are the above four the ones that JKR was thinking of, or are there more?
But these four are certainly enough to start with.
In the Harry Potter books, the behavior of these fathers certainly does seem to contribute to "evil" - to people whose morals leave something to be desired. Would these four children have grown up differently, though, if the situations and characters of the mother and father were reversed?
If Voldemort's father was the pure-blood, and his mother was a Muggle who abandoned him as a baby, and his father died shortly after he was born - wouldn't he hate Muggles just as much?
If it had been Snape's mother who was a Muggle, and showed resentment towards her son because he was a wizard and she was not, and because she was stuck in a relationship with a wizard, thrust into the wizarding world because, say, she was already pregnent with him - would he have resented Muggles any less?
If it was Petunia who was the more aggressive/abusive one, Vernon the one who just yelled and gave Harry chores to do, would Dudley have turned out differently? Well, maybe. Boys do tend to develop personality traits of their fathers.... But I doubt he'd be any better. He'd still be a horrible brat, and a bully as well.
If it had been Crouch Jr's mother who had ignored him, not paid him much attention, spent all her time in politics and gave him no attention... I think the affect would have been quite negative.
On the other hand.... I don't have hard data to back me up, but I seem to remember reading that children whose fathers abandoned the family are much more prone to crime, etc. than regular children - but even this doesn't really say much, because what statistics are there of children whose mothers abandoned them?
I actually do believe that a child's father and mother contribute differentlty (overlapping, but differently) to a child's development - but to say that evil tends to flourish when there's a lack of good fathering.... I think that anicdotal evidence in the world at large might prove that true, but only, I suspect, because fathers are so much more likely to abandon their families than mothers, so much more likely to be abusive, so there just aren't as many instances of really bad mothering. But maybe I'm wrong. Any data - or just personal opinions/views - would be very welcome.