The Philosophy of Spinoza · Benedictus de Spinoza
XXX
Since, therefore, those things are good which help the parts of the body to perform their functions, and since joy consists in this, that the power of man, in so far as he is made up of mind and body, is helped or increased, it follows that all things which bring joy are good. But inasmuch as things do not work to this end--that they may affect us with joy--nor is their power of action guided in accordance with our profit, and finally, since joy is generally related chiefly to some one part of the body, it follows that generally the emotions of joy (unless reason and watchfulness be present), and consequently the desires which are begotten from them, are excessive. It is to be added, that an emotion causes us to put that thing first which is sweet to us in the present, and that we are not able to judge the future with an equal emotion of the mind. Superstition, on the contrary, seems to affirm that what brings sorrow is good, and, on the contrary, that what brings joy is evil. But, as we have already said, no one, excepting an envious man, is delighted at my impotence or disadvantage, for the greater the joy with which we are affected, the greater the perfection to which we pass, and consequently the more do we participate in the divine nature; nor can joy ever be evil which is controlled by a true consideration for our own profit. On the other hand, the man who is led by fear, and does what is good that he may avoid what is evil, is not guided by reason.
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