1 Causa sui as the Real Movement of the Production of Reality

For Spinoza, the problem of the unity of Nature is the problem of immanent causality. God is productive force, and this force is life itself. This is quite different from how Renaissance thinkers defined life: an irrational and obscure élan vital that necessarily implies contingency. Spinoza cannot accept this definition, since, for him, ‘things could have been produced by God in no other way, and in no other order than they have been produced’. This argument is based on the identity of God's power and essence, already implied in the identification of God, cause of all things, with God, cause of itself:

The problems of a self-caused existence and infinity, or indetermination, are the same. Both are the absolute expression of an existence that includes the production of particular things. God cannot be the absolute expression of existence without also being the absolute expression of the existence of singular things. Precisely because ‘the absolute affirmation [affirmatio] of existence’ is at the root of being (real Being itself as absolutely infinite), there can be no chance; only this world could have ever existed. It is also why only this rationality can exist, which finds its raison d’être and necessity in the absolute affirmation of existence itself, in God's absolutely infinite nature. This explains how Spinoza can write to Hugo Boxel that ‘the world is a necessary effect of the divine nature and was not made by chance’. By ‘chance’ (fortuito), Spinoza means some failure to reach a goal, a deviation from the projected and originally pursued end. Chance refers to the unintended and unwanted effect of an action, a discrepancy between the pursued goal and the obtained result. In a teleological conception of the production of things, the notion of chance has the negative connotation of a deviation. Boxel defines chance in the following way: ‘something is said to have been made by chance when it does not originate from the agent's intention’. Spinoza uses the notion comparably: ‘in creating the world God had one goal, and [yet] he went completely outside the goal he had’.