If we become just a little objective and observational, we would notice that the materials which are man made were already created by material nature even though there are slight differences in the chemical formulas and physics processes. Consider if your skin is really a plastic bag, which if cut leaks fluid until the torn area is knitted again. We are discouraged from realizing that because it would challenge the self concept of "me." Imagine self-inquiry: Am I a plastic bag with fluids, flesh and bones in it?