Abstract
This paper discusses the significance for the philosophy of perception and aesthetics of certain productions of the ‘offline brain’. These are experienced in hypnagogic and other trance states, and in disease- or drug-induced hallucination. They bear a similarity to other visual patterns in nature, and reappear in human artistry, especially of the craft type. The reasons behind these resonances are explored, along with the question why we are disposed to find geometrical complexity and ‘supercolouration’ beautiful. The paper concludes with a plea on behalf of neuroaesthetics, but with a caution or two.