Looking for a quote about philosophy not being taught to people until age 35.

I'm looking for a quote from someone (I want to say Socrates or Aristotle; can't really remember) about how he thought philosophy shouldn't be taught to people until they were (I think) 35 years old, because anyone younger would use it to hurt others the way puppies try to bite at each other. Does anyone know the exact quote or where this is from? Thanks!!

EDIT: u/abomb-and-aplomb found it. It's in Plato's Book 7. Please see his comment for the full quote.