noun. The doctrine, set forth by David Hume and his successors, that percepts and concepts constitute the sole objects of knowledge, with the objects of perception and the nature of the mind itself remaining unknowable.

noun. The philosophical doctrine that the phenomenal and the real are identical —that phenomena are the only realities. Also called externalism.

noun. That theory which limits positive or scientific knowledge to phenomena only, whether material or spiritual.

noun. The doctrine that physical objects exist only as perceptual phenomena or sensory stimuli

"This sort of idealism is just the reverse of that which was held by the philosophers of antiquity and their Christian successors; it does away with the reality of ideal principles by confining them exclusively to the thinking subject; it is a spurious idealism which deserves rather the name "phenomenalism" (phenomenon, "appearance", as opposed to noumenon, "the object of thought")."

psychophysical phenomenalism