So’s we’re talking about Cartesian dualism in class and I gotta say, any type of dualism is nonsense. I’ll explain why I feel this way.
First of all, for those of you who aren’t familiar with dualism, it is basically the belief that there are two realms in the universe: the physical and the mental (or spiritual, for New Age dualists). These realms are totally distinct. The main issue with this sort of view is that if these realms are distinct, then there’s no way for them to interact without any sort of miracle. If you believe in miracles, then dualism may be your thang; if you believe in science and reason, you may have trouble buying this garbage.
I think dualism probably comes from the basic human desire for immortality. If there’s a part of us (which I shall henceforth call our “essence”) that is separate and distinct from the physical body, then it stands to reason that that essence can transcend the death of the physical body. This is highly unlikely, because as I will show, essence is inseparable from physical form.
Think of a pen. We could say that the essence of the pen is something like “to write things.” This is what it exists for, its essential something that makes it a pen. If I were to throw this pen into that massive junk grinder in 30 Days of Night and chop it up into a pile of scrap, would its essence still be writing? I think not. I don’t think it would have an essence any more. Therefore, it stands to reason that essence is a direct function of the physical form of a thing.
In the case of humans it may be more complicated, as the human form is an incredibly complex machine, but I think there is a universal human essence, or at least three essential quests with which all humans of normal psychology are concerned: the quest for truth, the quest for meaning, and the quest for pleasure. I think that all aspects of normal psychology can be reduced to these three essential quests.
Another rebuttal of dualism: Think of color. Color is not strictly speaking a physical thing. I arises when certain critters (such as humans) perceive certain wavelengths of electromagnetic radiation (light). Therefore, although it is distinct from light and perception, and although it is not strictly speaking a physical thing (nor does it “exist” in the strictest sense, as it requires perception to exist), it is easily reducible to physical phenomena.Remove the light or the perceiving entities and there is no such thing as color. The mind, therefore, can be thought of as similar to color, and entirely reducible to physical phenomena (perhaps certain chemical reactions in the brain). Remove these physical phenomena, and one has no mind.
In short, there is no reason to believe in an immortal spirit/soul/mind. The essence is a function of the physical composition of a thing, and is entirely reducible to physical phenomena.