Unfortunately, however, the term has been also employed to characterize another and distinct class of facts, namely _Co-[or Sub-]conscious Ideas_. We shall have occasion to study these psychological phenomena in other lectures.[134] We have seen examples in many of the phenomena I have cited. It is sufficient to say here, that as conceived of, and as we have seen, they are very _definite states of coconsciousness—a coexisting dissociated consciousness or coconsciousness of which the personal consciousness is not aware_, i.e., of which it is “unconscious.” Hence they have been called “unconscious ideas” and have been included in the unconscious, particularly by German writers. But this is plainly using the term in a different sense—using it as a synonym for the longer phrase, “ideas we are unaware of,” and not as a characterization of that which is physiological and non-psychological. “Unconscious ideas” in this sense (the equivalent of coconscious ideas) would include conscious states that we are not aware of simply because not in the focus of attention but in the fringe of the content of consciousness. The term would also include pathologically split-off and independently acting coconscious ideas or systems of ideas such as occur in hysteria, reaching their apogee in coconscious personalities and in automatic writings. Here we have a series of facts essentially different from the conceptual facts of physical residua, the form in which experiences are conceived to be conserved. Manifestly it is confusing and incorrect to define both by “the unconscious.” And to speak of the former as “unconscious ideas” and of the latter as “unconscious,” although technically correct, leads to confusion from using the term “unconscious” in two different senses.[135] As a concept in a scheme of metaphysics, “unconscious ideas”—i.e., ideas of which we are not conscious, have long been recognized. Leibnitz was the first to maintain, on theoretical grounds and by _a priori_ reasoning, the existence of ideas of which we are not aware, as did likewise Kant, influenced by Leibnitz, and later Schilling, and Herbart; while Hartmann evolved the unconscious into a biological and metaphysical system.[136] By most American, English, and French psychologists such ideas, as conceived at least by Leibnitz, Kant, and Herbart, would to-day be called subconscious or coconscious ideas. Hartmann included all physiological processes of the nervous system in the Unconscious and ascribed to them special attributes (will, purpose, etc.). The Unconscious accordingly has connotations from which it is not easy to rid ourselves in dealing with it. It is generally agreed that it is desirable to have a term which shall cover all classes of facts—coconscious ideas, conserved experiences, and physiological processes—without committal of opinion as to interpretation.[137]