Substance Dualism Is Not The Whole Of Metaphysics

It is an act of immense ignorance to treat all things that exist as if they are ultimately comprised of either consciousness or matter.  There are at least three things that fall into neither category, existing within categories of their own.  Substance dualism, which acknowledges the inherent differences between consciousness (also termed mind) and physical matter, is significant, but it by no means encompasses the whole of metaphysics.  There are at least three things, all of them immaterial, that are distinct from both mind and matter--though very few come to realize this, as with almost all details beyond those which are utterly foundational to a subject.

Logic is the most important of these three things.  Even space, which I will address next, could not exist without logic, as space could not be space apart from it!  Logic is the one thing which cannot not exist even if all other things [1], including any other necessary existents (an existent is a thing that exists), did not exist.  One does not even need to establish that matter exists to refute metaphysical solipsism: since logic exists in the absence of minds, it cannot be a component of a mind.  The intellect grasps the laws of logic, but logic is not the intellect.

Space is not only immaterial, but it, just like logic, has to exist, since it is impossible for there to be such a thing as the nonexistence of space [2].  Since space is not matter, though it is required for matter to exist in any form, and and since space exists independent of all consciousnesses, it too falls outside of the scope of substance dualism.  References to space as an independent, necessary existent are practically unheard of in the history of philosophical literature, as with logic, but the matter remains important.

Time, unlike logic and space, does not have to exist; it would have been possible for it to have never existed and it could cease to exist.  The fact that the present moment cannot be an illusion proves that time does exist, nevertheless.  Since it is a duration that elapses, time cannot be a consciousness itself, since a perceiving mind and a duration of moments are not identical.  Time is neither a conscious being nor an object/environment fashioned from any material substance [3].  As with the previous two examples, that time is separate from the mind-body dichotomy is obvious upon serious reflection.

Substance dualism is a crucial and major truth, but there are multiple things which metaphysically exist that extend far beyond its limited scope.  It is impossible for every immaterial thing to be a part of a mind, and it is impossible for an immaterial thing to be constituted of matter.  Clearly, at least two immaterial things exist whether or not any consciousness or matter exist alongside them, since they are necessary existents.  Substance dualism, therefore, cannot summarize or represent everything that exists.  The boundary between truth and falsity demands that I emphasize this point because I do not expect many others to do so.

[1].  https://thechristianrationalist.blogspot.com/2017/10/the-immateriality-of-logic.html

[2].  https://thechristianrationalist.blogspot.com/2018/09/a-refutation-of-naturalism-part-2.html

[3].  https://thechristianrationalist.blogspot.com/2018/07/the-immateriality-of-time.html