Selection from – Ethics – Part III. On the Nature and Origin of the Emotions (Page 2)

Spinoza's Words: (nature is studied by reason, emotions can be studied in the same way)

I wish to turn to those, who would rather abuse or deride human emotions than understand them. Such persons will, doubtless think it strange that I should attempt to treat of human vice and folly geometrically, however, such is my plan. Nothing comes to pass in nature, which can be set down to a flaw therein; for nature is always the same, and everywhere one and the same in her efficacy and power of action; that is, nature's laws and ordinances, whereby all things come to pass and change from one form to another, are everywhere and always the same; so that there should be one and the same method of understanding the nature of all things whatsoever, namely, through nature's universal laws and rules.

Thus the passions of hatred, anger, envy, and so on, considered in themselves, follow from this same necessity and efficacy of nature; they answer to certain definite causes, through which they are understood, and possess certain properties as worthy of being known as the properties of anything else, whereof the contemplation in itself affords us delight. I shall, therefore, treat of the nature and strength of the emotions according to the same method, as I employed heretofore in my investigations concerning (Deus sive Natura) and the mind. I shall consider human actions and desires in exactly the same manner, as though I were concerned with lines, planes, and solids.