'They claim that they perceive a mode of being superior to your existence on this earth. The mystics of spirit call it “another dimension,” which consists of denying dimensions. The mystics of muscle call it “the future,” which consists of denying the present. To exist is to possess identity. What identity are they able to give to their superior realm? They keep telling you what it is not, but never tell you what it is. All their identifications consist of negating: God is that which no human mind can know, they say — and proceed to demand that you consider it knowledge — God is non-man, heaven is non-earth, soul is non-body, virtue is non-profit, A is non-A, perception is non-sensory, knowledge is non-reason. Their definitions are not acts of defining, but of wiping out.'
-- Ayn Rand, For the New Intellectual, p. 148