Iealism is the doctrine that ideas, or thought, make up either the whole or an indispensable aspect of any full reality, so that a world of material objects containing no thought either could not exist as it is experienced, or would not be fully "real." Idealism is often contrasted with materialism, both belonging to the class of monist as opposed to dualist or pluralist ontologies. (Note that this contrast between idealism and materialism has to do with the question of the nature of reality as such — it has nothing to do with advocating high moral standards, or the like.)