Right at the heart of you and I is desire. Thus says Spinoza, Schopenhauer and the Buddha. It only needs brief observation of the inner state to see this is true. Sit and watch the desires come and go – they are endless with one feeding into another. Spinoza had a wholly different take on desire to Schopenhauer however, and it is worth exploring. For Spinoza “desire is the essence of man”, and particularly the desire to persist in existence. Each creature is given what he calls a “sovereign natural right” to exercise whatever power it has. The strong shall dominate and exploit the weak, and Spinoza sees nothing amiss in this. Nature, after all, has made each creature the way it is – we do not self-create. As such, since Spinoza equates this power of existence with God, he considers that the strong dominating the weak is a God-given behavior. In fact, Spinoza equates the power for existence with virtue. However, all is not rosy in this garden. We can’t always get what we want, and so we suffer. And we cannot have a free-for-all in human life, or we suffer like beasts. So we have to sacrifice some of our power to the State in order to have an orderly society. Spinoza is telling it as-it-is, with no apologies and no value judgment. This is the way things are and so we had better organize our lives so we suffer as little as possible.
Schopenhauer takes a wholly different approach. He was heavily influenced by Eastern religions and particularly Buddhism. So his take goes something like this. Our bodies are desire manifested in time and space. This desire is the same in all things, and he called it the will-to-life. This is a blind, unconscionable force, causing each creature to see itself as the center of the universe. In order to exist creatures have to impose suffering on other creatures (eat them, exploit them, fight for dominance, mating rights etc). He sees the whole thing as completely lamentable, and while any creature is driven by this force it will suffer and cause other creatures to suffer. And so, at the end of his masterwork, The World as Will and Representation, he proposes the denial of the will-to-life. In other words, something within us looks at this blind force and turns away from it. Obviously, this is similar to renunciation in the Christian religion, and most religions have some form of this. Of course, it is very rare that any individual can do this, but maybe the Saints and some sages have turned away from the will-to-life.
Each approach has its merits. Spinoza simply insisted that we exercise our power as much as possible, and simply bear the fact that it isn’t always possible to get what we want. Schopenhauer is effectively advising that we suffer the pain of denial up-front while seeking liberation from all desires. Personally, I take what is useful from both approaches. Schopenhauer sets before us the terror of the situation and gives an emotional angle, whereas Spinoza presents a rational approach with methods for dealing with desires.
In summary, Spinoza sees desire as legitimate and he deals with it as it is. Schopenhauer sees desire as a blind and ruthless thing, and if possible it should be denied.