Are all evil doers evil for the same reason? [closed]

Question

In Normal Mailer's book "The Castle In The Forest" he explores the source of Hitler's evil. While it takes a while for him to get to the point he eventually concludes that (spoilers) the only two ingredients necessary are a large amount of pride and maybe a dose of ignorance. Everything else spawns from this. That is to say, a good person and an evil person can live nearly identical lives and the only difference between the two of them is a little pride or humility.

Examples

• Doctor Octopus - Kept insisting that his machine worked fine. (I'm trying to keep the spoilers down but we know what happened here.)

Even good characters can display moments of evil when they get a little prideful.

• Doctor Who - Decides for a moment that he can do whatever he wants and saves that woman from the mars expedition.

I was thinking that perhaps a good answer would be that most evil characters have one of the so called "7 deadly sins", but couldn't the first 6 be caused by the 7th, which is pride?

EDIT: I've accepted an excellent answer, but to narrow this down further let's ask if pride is what pushes evil characters to the very edge of the evil spectrum. Is it a necessary ingredient to make one a super villain?

Answer 1

• Voldemort. He's a sicko from a pretty nasty home, and he's determined to take it out on everyone else in existence.

• The Dark One in the Wheel of Time (and his analog in The Sword of Truth) is the embodiment of withering destruction. He isn't making some grand mistake, he's simply a force of nature that needs to be kept in check.

• Richard in Looking For Group gleefully enjoys killing people for its own sake.

But he also needs to kill people to keep his powers, but he also enjoys it

• Black Mage in 8-Bit Theater is willfully, knowingly evil. His main power drains the total love in the world as its fuel. He was so evil that hell itself voted him out.

• Makuta Teridax in the Bionicle-verse is simply greedy, from start to finish.

• Many villains in the Dresden Files, but not all of them, enjoy being evil. Notably, the path to being a Warlock (evil wizard) almost always starts with pride + ignorance, especially because there are too many to train to be good guys given how fast the world has grown in the last century. The ones who don't fit the question's characterization are often simply predators that need to be permanently separated from their prey.

• Many of the villains in the Artemis Fowl series are greedy, but not prideful.