There is beauty. Beauty in reality, and beauty in art. If you are familiar with Rand's views on esthetics you will understand that art has a purpose and a value to man, and what that purpose is.
Irrationality as such, which is something completely distinguishable from art, fiction, and imagination, is not beautiful. There is a world of difference between celebrating life by engaging in imagination, fiction, contemplating a flower or a seascape etc. and abandoning life by choosing to live in a drugged stupor, an induced euphoria, or a blind ignorant false existence. Beauty lifts one