For the Greeks, “phantasia” denoted this special faculty in the mind for producing poetic, abstract, and religious imagery. Phantasia is our capacity to ” make visible” the contents of the inner world by giving them form, by personifying them. The Greek took for granted the reality of the inner world, expressed as ideal forms or universal qualities that clothed themselves in the divine images of their gods. For them, phantasia was the organ by which that divine world spoke to the human mind.
Yet, for some peculiar reason, we have lost the concept of the reality associated with fantasy and turned it into this:
Fantasy: “the power or process of creating especially unrealistic or improbable mental images in response to psychological need<an object of fantasy>; also : a mental image or a series of mental images (as a daydream) so created.