iii — Section 34

A man should see himself as a kind of tool-box; this is simple enough; the difficulty is that it is the tools themselves that make and work the tools.  The skill which now guides our organs and us in arts and inventions was at one time exercised upon the invention of these very organs themselves. Tentative bankruptcy acts afford good illustrations of the manner in which organisms have been developed.  The ligaments which bind the tendons of our feet or the valves of our blood vessels are the ingenious enterprises of individual cells who saw a want, felt that they could supply it, and have thus won themselves a position among the old aristocracy of the body politic.

The most incorporate tool—as an eye or a tooth or the fist, when a blow is struck with it—has still something of the non-ego about it; and in like manner such a tool as a locomotive engine, apparently entirely separated from the body, must still from time to time, as it were, kiss the soil of the human body and be handled, and thus become incorporate with man, if it is to remain in working order.