Excepting man, we know no individual thing in Nature in whose mind we can take pleasure, nor any thing which we can unite with ourselves by friendship or any kind of intercourse, and therefore regard to our own profit does not demand that we should preserve anything which exists in Nature excepting men, but teaches us to preserve it or destroy it in accordance with its varied uses, or to adapt it to our own service in any way whatever. XXVII The profit which we derive from objects without us, over and above the experience and knowledge which we obtain because we observe them and change them from their existing forms into others, is chiefly the preservation of the body, and for this reason those objects are the most profitable to us which can feed and nourish the body, so that all its parts are able properly to perform their functions. For the more capable the body is of being affected in many ways, and affecting external bodies in many ways, the more capable of thinking is the mind. But there seem to be very few things in Nature of this kind, and it is consequently necessary for the requisite nourishment of the body to use many different kinds of food; for the human body is composed of a great number of parts of different nature, which need constant and varied food in order that the whole of the body may be equally adapted for all those things which can follow from its nature, and consequently that the mind also may be equally adapted to conceive many things. XXVIII The strength of one man would scarcely suffice to obtain these things if men did not mutually assist one another. As money has presented us with an abstract of everything, it has come to pass that its image above every other usually occupies the mind of the multitude, because they can imagine hardly any kind of joy without the accompanying idea of money as its cause. XXIX This, however, is a vice only in those who seek money not from poverty or necessity, but because they have learned the arts of gain, by which they keep up a grand appearance. As for the body itself, they feed it in accordance with custom, but sparingly, because they believe that they lose so much of their goods as they spend upon the preservation of their body. Those, however, who know the true use of money, and regulate the measure of wealth according to their needs, live contented with few things. XXX