OVERANALYZING THE TEXT

Kristin (who was right the first time) wrote:

Hagrid tells Harry that "there wasn't a wizard that went bad who wan't in Slytherin." And at this time, Sirius Black had not yet been proven innocent. We know that Hagrid knew about Sirius' alleged crimes and that he was most certainly considered a bad wizard in his eyes, so for him to make this statement he must have known Sirius to be in Slytherin.

Yes, well. Hagrid also says that foreigners cannot be trusted, that Harry must be a magically-powerful wizard for the simple reason that his parents were, and that the Malfoys all have "bad blood." (I find that last comment particularly rich, given what we now know about what Hagrid's got running through his own oversized veins.)

In short, Hagrid is an unthinking bigot. He is partial to sweeping generalizations, and he does not stop to consider their ramifications. I would imagine, for example, that he would be genuinely hurt to be accused of adhering to the pureblood aesthetic of the Malfoys and their ilk, even though that is precisely the sort of thinking that his comments all too often reflect.

Nor does Hagrid take any particular care to make certain that his statements are in the least bit accurate. In truth, the fact that Harry's parents were magically powerful is no assurance that Harry himself will be: Squibs exist, and they can come from the very best families, right?

I think it strongly suggested from the way that Sirius refers to House Slytherin and its members that he was not himself a member of that House.

—Elkins