A lot of writers who need a Hero Team in their story know that you have to give each member some unique traits, 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 because I can only think of one example that's not mine) is "philosopher". The example is Ham in Mistborn.
The reason I felt the need to write about this is because the author doesn't take Ham seriously as a philosopher.
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 start interesting discussions that bring out the other characters' interesting traits. He's using him to ridicule philosophy. It's garbage.