Metaphysical Materialism reflects our common sense understanding that Reality just is the world that we see, hear, smell, touch, and taste, as well as the more imperceptible components (e.g., molecules, atoms, and the sub-atomic) of which modern science informs us. This is also the oldest metaphysical account of the Universe, going all the way back to that first philosopher, Thales. But, as we learned in Chapter 1, Philosophy is not merely about 'common sense' views or idle speculation; Philosophy is a discipline of arguments. Therefore, before we acquiesce to the Materialist view, we should examine and analyze their argument(s).
The basic argument for metaphysical materialism:*
This outline is taken from Epicurus’ Materialist arguments—see the Epicurus’ "First Principle of Materialism"—summary that follows.
*For a full summary of Epicurus' arguments for Materialism, go to the Epicurus Link above.
Although this argument is valid, it may not be sound. That is, the premises may not all be true. For example, what is the justification for believing premise 1? Usually, collective empirical observation is appealed to here as Epicurus does. Do your senses and your memory of past experiences tell you that things can just appear and disappear without some other material cause? Most of us would probably follow modern science and agree to this premise. What about premise 2? Again, our senses seem to confirm this and few would argue this claim. However, premise 3 seems problematic. Our senses are of no help here, since if our minds do produce reality, that reality would most certainly still involve the senses or at least appear to. Furthermore, the mental, by its very nature, is non-physical, non-material, thus the materialist cannot merely incorporate 'mind' into her materialist universe (see discussions of dualism and the mind in Soccio chapter 10). How could we ever be sure since we cannot 'step outside' our senses to check? Indeed, premise 3 seems to beg the question since it is only entailed by the Materialist conclusion; thus there is a hint of circularity here. But if it is left out of the argument, then the possibility that there might exist something non-material remains and so we cannot draw the materialist conclusion. Premise 4 also seems problematic since there is no way to confirm it. Yet if the universe is finite, then we can sensibly ask what is beyond it or what comes before or after it. Such a question again opens the possibility to non-material existence since the universe is supposed to contain all that is material. Thus this premise also seems necessary for the argument, but there seems no reason to believe it. Finally, premise 5 seems proper since it does appear that premises 1-4 are sufficient to entail the conclusion. Can you think of any other conditions that would further promote Materialism? However, premises 3 and 4 should produce enough doubt to make us skeptical of the Materialist view. We shall have to see if the Idealist does any better.
A note about the implications of Materialism:
Soccio does a fine job of explaining the implications of Metaphysical Materialism. This is an especially important discussion since it makes the point that how we understand the basic nature of reality determines to a large extent the way we understand the rest of our existence. Consider the arguments used to draw the various conclusions from the materialist position. For example, if materialism is correct, then there seems no justification for belief in God. For if the entire universe is composed of and can be explained by matter and material forces, then there is no role for God to play. The universe has always been, hence no creation, and always will be, hence no second-coming or whatever. Gassendi attempted to argue around this, but notice the God he leaves us with seems far different than what Christians and Muslims worship since it suggests a God who takes little interest in our World. Furthermore, if God did create the material Universe, what existed before it? Where does God reside? Is God part of the temporal realm? Do you maintain a materialist view of the Universe and also a religious belief in God? Are these two beliefs consistent? If not, doesn't reason demand that you give up one of them?
What about free will? If everything in the universe is material and so attributed to material forces, there cannot be free will. That is, to have free will is to do certain things only because my will determined from a set of alternatives which action to take and I could have acted differently had I so willed it. But if there is only matter, then my actions must be the result of material forces, not something so ethereal as the 'will.' Again, it appears inconsistent to believe in free will and materialism. Which would you give up? Would you give up materialism in order to continue believing that some of your actions are actually under your control? Or would you maintain you belief in materialism and become a determinist?
Such discussions provide excellent examples of what Philosophy does since they show how Philosophy analyzes our most basic beliefs and holds them to the standards of reason, e.g., consistency.