1. (n.) The doctrine that immaterial substances or spiritual being exist, or are possible.

2. (n.) The doctrine that external bodies may be reduced to mind and ideas in a mind; any doctrine opposed to materialism or phenomenalism, esp. a system that maintains the immateriality of the soul; idealism; esp., Bishop Berkeley's theory of idealism.

Berkeleianism Hegelianism Kantianism Neoplatonism Platonic form Platonic idea Platonism absolute idealism allotheism animatism form heathendom heathenism heathenry hylozoism idealism idolatry immaterialism metaphysical idealism monistic idealism pagandom paganism paganry panpsychism personalism psychism solipsism spiritualism subjectivism transcendental universal