"All the boys seemed to him very strange. They had all fathers and mothers and different clothes and voices. He longed to be at home and lay his head on his mother's lap. But he could not: and so he longed for the play and study and prayers to be over and to be in bed." - p. 25-26 A Portrait of the Artist as a Young Man by James Joyce.
I can relate somewhat to this passage. When all else fails, it seems that sleep is the only escape, the escape being in to one's own thoughts and dreams. To me, this seems to be a clear starting point for the growth of an intellectual mind. The mind in question is, of course, Stephen Dedalus. The intellectual growth arises through the constant dwelling within one's thoughts, and therefore allowing for an expansion of ideas.