17. It would be impossible to itemize or classify the good or bad fluids. Neither could we specify their respective qualities, considering that their diversity is as great as that of the thought.
Fluids do not have “sui generis” qualities, except those they acquire whereat they are elaborated; they are modified by the effluviums of the ambient, just as the air is modified by exhalations, and the water by the layers of salt it crosses. Depending on the circumstances, their qualities are, like those of the air and the water, either temporary or permanent, which makes them more suitable for the production of certain specific effects.
Neither do the fluids have special denominations. As with odors, they are designated by their properties, their effects and their original type. On a moral point of view, they bring the impressions of the sentiments of hatred, envy, jealousy, pride, selfishness, violence, hypocrisy, kindness, benevolence, love, charity, sweetness, etc. On a physical point of view, they are excitants, sedating, piercing, coercing, irritant, soothing, soporific, narcotics, toxics, replenishing, and expellants. They also become a means of transmission, propulsion, etc. The overall picture of the fluids would then be that of all passions, virtues and vices of humanity; and that of the properties of matter, corresponding to the effects they produce.