We know the narrator of "De Daumier-Smith's Blue Period" only by his pseudonym, Jean de Daumier-Smith. This kind of thing is usually a clue that identity is a serious issue. At nineteen, Jean is faced with the death of his mother. Being motherless is an identity he has no desire to experience. Yet, because she is dead he must find away to deal with this new identity or go down the tubes. Jean deals with the situation creatively, by dreaming up an alternative identity that he can live in while he figures things out. On top of dealing with his mother's death, Jean is also dealing with the customary difficulties most people in their late teens deal with. Jean's struggle in this story is about learning to be an adult without giving up a playful and creative way of looking at the world. Along the way he experiences a series of transformational moments (a.k.a. epiphanies) as he deals with seat-less busses, novice art students, and the fact that there are no chairs in his bedroom.
A big part of Jean's identity is lying; by faking his identity and lying all the time, he hides from his problems.
Jean's lies are not to be taken as literal "lies," but rather as stories, thus highlighting his talent as a writer, in addition to his talent as a visual artist.