Guys. I know many of you shame Salazar for choosing not to allow muggleborns.

But my theory is that he had good intentions. Slytherin probably said that when people believed witches were real. He was afraid that a muggleborn might rat Hogwarts out. And that could mean the extinction of wizards.

And Slytherins like to weigh the pros and cons. In other words they're cautious. The oppisite of cautious is reckless. In other words Gryffindors. Gryffindor probably didn't put much thought into his actions and they fought.

The Chamber of Secrets could have been a last resort if muggles attacked Hogwarts.

And sometimes good intentions get twisted. For example, in Divergent, the faction Dauntless was for those brave enough to protect those who aren't. But now it's more "I'm going to throw a knife at you. Don't flinch.". So the pureblood thing may have been twisted like that.

In conclusion, Slytherin may have not been evil after all.

Comment if you agree with my theory.