What are the three main aesthetic principles put forward by Stephen in A Portrait of the Artist as a young man?

A book entitled
The Future of Modernism, edited by Hugh Witemeyer, answers this very
question:

"In the notebooks of 1903-4 Joyce articulated the aesthetic
principles that Dedalus defends . . . that any theory of beauty must encompass the
conventionally ugly; that art is neither immoral or amoral but beyond conventional morality;
that the work of art should be a wholeness, 'selfbounded and selfcontained'; and that the third
of Aquinas's three phases of aesthetic apprehension must be understood (or changed) to mean not
enjoyment but stasis, 'the luminous silent stasis of estheic pleasure'"
(40).

That's actually four principles, but I hope this
helps.

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