I want to go on to introduce Emerson’s Idealism, but before I do I need to get a few things straight, namely the distinction between Idealism, Materialism, Rationalism, Empiricism, Realism, Nominalism, Dualism and Monism. In the study of philosophy these words come up often and it can be challenging at times to keep them all straight. That is partly because some of their meanings are separated by subtle distinctions and partly because some of them have both a technical philosophical meaning and a more common meaning that seem to conflict.
So for all of our sake lets walk through them slowly.
First of all they are all generally related to one of the most foundational philosophical dualisms there is – mind and matter. At least since the ancient Greeks the problem of mind and matter, thought and thing, the spiritual and the material, has existed. And as long as that dualism exists – and it has, for the record dramatically fallen out of favor – the fundamental question that needs to be tackled is, “Which is more real? Mind or matter?”
Idealism is the belief that the mind and ideas is the primary structure of reality and that physical or material reality is secondary.
Materialism is the opposite of Idealism and sees matter as the primary reality and all other things including thoughts as the product of interactions of matter.
Rationalism is the belief that the rational mind is the best way to know something. If you are a rationalist you believe that your mind is more trustworthy than your sense. A stick in the water might look bent, but you know rationally that it only looks that way because it is in the water.
Empiricism is the opposite of rationalism and it is the belief that the senses are the best way to know something. You might think something is true, but you only know it is true if your senses confirm it.
In consideration of the above it is good to keep in mind that you can’t be an Idealist and a Materialist and you can’t be a Rationalist and an Empiricist. On the other hand, you can be an Idealist and a Rationalist or an Idealist and an Empiricist. You can also be Materialist and a Rationalist or you can be a Materialist and an Empiricist.
That is because Idealism and Materialism are statements of ontology which means they are statements about what you believe is real. Rationalism and Empiricism are statements of epistemology which means statements about what is the best way to know what is real.
As if this were not confusing enough we also have Realism and Nominalism.
Realism is the belief that there are real existing entities behind universal or general ideas. For instance there is a “thing” called justice. Nominalism on the other hand is the opposite and it is a belief that there are no real existing entities behind universals. There is no “justice” per se, there are just individual instances of justice. Only the individual instances of justice are real.
Now for our last two terms we have Dualism and Monism. Dualism is the belief that mind and matter represent two different and distinct types of being. Monism is the belief that there is ultimately only one type of being. If you are a Monist you could also be an Idealist which means that you believe that everything is made up of mind or ideas, so even matter is ultimately made up of ideas. A monist could also be a Materialist believing that all ideas are ultimately products of matter.
OK, that should be enough to get us started.