Plato was in some ways the original metaphysical dualist in Western thinking. His philosophy was based on the fundamentals conception of ideal form and as such he can be seen as one of the earliest thoughts in a conversation about the ideal reality that abides behind the reality of appearance known as Idealism Plato’s reasoning was simple. The only way we could know anything is if there already existed in the mind some notion of the ideal form of that thing. How do we know that a tree is a tree when we see it? We only recognize it as a tree because it matches our inner image of ideal “tree-ness.”
Plato was a student of Socrates and that is where this fundamental notion came from. Socrates believed that the mind already contained all knowledge and so his “Socratic” method of inquiry was designed to ask questions that would draw out the knowledge that was already in the mind. Truth, Beauty and Goodness were some of the big ideal forms that the mind contained, as was the idea of justice. How do we know what is true, what is beautiful, what is good or what is just? Some might say that we are taught these ideas from our society and certainly that is true and both Plato and Socrates recognized that. They also recognized that your society might teach you one thing and you might believe something else. Your society might tell you that going to war is just and you might believe it is unjust. How were you able to do that? In Plato’s thinking you can only do that because you have some innate ideal sense of justice already in your mind to appeal to that exists outside of what you have been taught.
Plato was a dualist in that he believed that the reality that we saw with our senses was an imperfect expression of a hidden world of ideal form. This hidden world of ideal form existed as the deep wisdom of the mind. This kind of dualism is reflected in the later ideas of Descartes, Kant, Hegel and other Idealist philosophers.
Aristotle challenged Plato’s dualism in some ways and his came with a different sense of what was ultimately real. Plato felt that what was ultimately real was the ideal form of things. Everything had an ideal form that existed behind the thing itself. Aristotle had a different sense of the ideal because he believed that the most fundamental aspect of reality had to do with the dynamics of change. Aristotle was captivated by the process of becoming. Things change and so the ideal of a thing, a thing’s nature, is not some hidden form behind it, but the force of change that can take it to its ultimate form in time. The nature of an apple seed rests in its potential to become an apple. What would a thing become if the natural process of change were allowed to progress to its ultimate end? That is the question that gives us a thing’s ideal form. The ideal form of a thing, its nature, is whatever it is destined to become through the process of natural change. In this sense then the ideal form of a thing is not something that exists in some separate realm, it is an innate part of the thing itself. In this sense Aristotle did away with Plato’s duality.
Aristotle’s thinking has a love/hate relationship with the modern conception of science that we have spent some time discussing already. On the one had Aristotle in his belief that change was most fundamental in reality was always motivated to observe how things changed, how they developed, grew and evolved. The question that naturally arises from this investigation is “what is the cause of change?” Why causes change? This was the question at the heart of Aristotle’s science and we still see the dominance of this question in science today. At the same time Aristotle attributed change to an innate nature of things. He believed in animism – the idea that all things are animated from within. This led him to believe for instance that objects fall because it makes them happier to be closer to the earth. So Aristotle’s thinking would tend to attribute animal qualities to Aquinasinanimate things. And it was in reaction against this idea that modern science would eventually be born.
Aristotle also became central to Christianity during the middle ages. The question of ultimate cause was picked up by the Christian thinker Thomas Aquinas while he was attempting to rectify Aristotle’s thinking with Christian doctrine. This synthesis of thinking would become the dominant intellectual paradigm throughout the Western middle ages. And Aquinas would eventual come to define God in Aristotlilian terms as the “first cause” or the “uncaused cause.”
Let’s link Aristotle more directly to William James. Aristotle’s investigation into the nature of causes led him to realize that there was a hierarchy of being. The lowest level of the chain was inanimate things and in examining the causes of change in these types of objects it is clear that they only change when acted upon. So a rock for instance if thrown into the air would stop and come back down, but it would never throw itself into the air. The next level of the chain was plants because these would act when acted upon like non-living things, but they would also grow all on their own. You plant a seed and it contained the cause for it to grow into a flower. Animals were next in the chain because not only could they be acted upon like rocks, and grow like plants, but they could also choose to do things, walk, run, sleep, eat, etc.
Human beings were highest on the chain because human beings are not only acted upon, grow and act, they also choose what they should become. Human beings have the unique ability to be concerned about themselves and to make choices about how they should live and what they will become. The nature of being human rested in our ability to cause ourselves to be a particular kind of person. The fulfillment of human nature to Aristotle rested in become the person you are most supposed to be This ability to choose who you will be is absolutely central to James’ thinking, as it was to the Romantic American Transcendentalists whose shadow he was traveling in..