A lot of writers who need a Hero Team in their story know that you have to give each member at least one meaningful distinctive trait, and if there are more than three this can be difficult. A common trait to lump on one of them (okay, maybe it isn't actually that common) is "philosopher". For example Ham in Mistborn, Elijah in my own novel Pillars of Life.
I don't think this is inherently a bad idea (although it's not enough by itself to make a fun character; Ham had other traits and Elijah was lacking as I'll admit most of the characters in that novel were). My problem is that a lot of authors don't take the philosopher character seriously, and Ham is a perfect example.
Ham asks deep-sounding questions that neither he nor the other characters ever make a serious attempt to answer. Worse, many of the questions he asks only sound deep to someone who doesn't have a real appreciation of philosophy and are actually retarded, like when he says "We're fighting the Lord Ruler because he's evil, but as God, he defines good and evil. Are we evil, or does wrong actually count as right in this case?" No real philosopher thinks being a "God" (a word that loses its meaning anyway in this context) makes you define morality. Even if you did, Ham has already answered his own question: his final clause is proof that he believes in a standard of morality that's above "God". But the other characters are stumped, and the conversation moves on and nobody ever discusses this again.
Or when he asks who is responsibile for a crime committed by someone under partial mind control and not one person considers that the answer might be "both". That conversation ends the same way.
Sanderson isn't using his philosopher character to incite interesting discussions that bring out the other characters' interesting traits. He's using his character just to make fun of philosophy. It's garbage.
There are again lots of criticisms you could make of Elijah and the conversations he starts. But at least they lead somewhere and don't insult philosophy. When he starts a discussion about the origin of the world, he has already thought more about this than most theists. The question he asks is legitimate and doesn't have an obvious answer. And the conversation is used to somewhat develop other characters: David, Elijah's brother, shows disdain for this kind of rumination and - unlike most characters who do this - he says it in response to something that makes the attitude understandable even to someone who enjoys this stuff. Yet he still can't help but contribute one line of meaningful thought when it jumps out at him (we know from later conversations that he's upset about his brother being more powerful than him, so we can understand that he wants to feel superior to his brother in his brother's own intellectual arena to make up for it). Katherine banters insulting both David and Elijah, showing that she doesn't have a strong interest in trying to answer the question but enjoys the conversation just for the way it brings out everyone else's personalities. Jaydin, the POV, contributes a possible insight, so I show that the designated philosopher character isn't the only one who cares.