Baruch Spinoza

I should attempt to treat human vice and folly geometrically… the passions of hatred, anger, envy, and so on, considered in themselves, follow from the necessity and efficacy of nature… I shall, therefore, treat the nature and strength of the emotion in exactly the same manner, as though I were concerned with lines, planes, and solids.

As men’s habits of mind differ, so that some more readily embrace one form of faith, some another, for what moves one to pray may move another to scoff, I conclude … that everyone should be free to choose for himself the foundations of his creed, and that faith should be judged only by its fruits.

If the way which I have pointed out as leading to this result (i.e., power over the emotions by which the wise man surpasses the ignorant man) seems exceedingly hard, it may nevertheless be discovered. Needs must it be hard, since it is so seldom found. How would it be possible, if salvation were ready to our hand, and could without great labour be found, that it should be by almost all men neglected? But all things excellent are as difficult as they are rare.

Since love of God is the highest felicity and happiness of man, his final end and the aim of all his actions, it follows that he alone observes the divine law who is concerned to love God not from fear of punishment nor love of something else, such as pleasure, fame, ect., but from the single fact that he knows God, or that he knows that the knowledge and love of God is the highest good

From what has been said we can clearly understand the nature of Love and Hate. Love is nothing else but pleasure accompanied by the idea of an external cause: Hate is nothing else but pain accompanied by the idea of an external cause. We further see, that he who loves necessarily endeavors to have, and to keep present to him, the object of his love; while he who hates endeavors to remove and destroy the object of his hatred.

Whatever increases, decreases, limits or extends the body’s power of action, increases decreases, limits, or extends the mind’s power of action. And whatever increases, decreases, limits, or extends the mind’s power of action, also increases, decreases, limits, or extends the body’s power of action.