He doesn't preach or try to decide what people should do; he presents a situation and then gets each individual to use their knowledge, background, and experience to decide how they should handle it. It should be noted that he's the only professor in the movie, and we rarely even see his classroom. The reason for this is that the campus society, the groups of similars banded together against one another, are the key element that molds each new class. Phipps knows how to guide students in the right direction, but he's the lone combatant against this stratified senselessness.
Another positive influence on Malik surprisingly comes is Ice Cube's character Fudge. I say that because Fudge initially seems like a big-mouthed punk slacker that will never graduate. Fudge is not the kind of person you want to room with. He does what he wants whenever he wants; he's incredibly selfish and inconsiderate to anyone who isn't in his group. He is at odds with the world, but he knows exactly why and is able to convey this knowledge. Although not nearly as memorable, Cube is in the vein of Woody Harrelson: capable of playing one type of character really well but hardly a chameleon. John Singleton is the director who launched his career though, and he knows what he is and isn't capable of. One of Fudge's messages is that you have the right to be treated equal. Fudge