Inorganic matter seeks only rest. "Let me alone," it says; "do not break my slumbers." But as soon as life awakens in it, it says: "Give me room, get out of my way. Ceaseless activity, ceaseless change, a thousand new forms are what I crave." As soon as life enters matter, matter meets with a change of heart. It is lifted to another plane, the supermechanical plane; it behaves in a new way; its movements from being calculable become incalculable. A straight line has direction, that is mechanics; what direction has the circle? That is life, a change of direction every instant. An aeroplane is built entirely on mechanical principles, but something not so built has to sit in it and guide it; in fact, had to build it and adjust it to its end. Mechanical forces seek an equilibrium or a state of rest. The whole inorganic world under the influence of gravity would flow as water flows, if it could, till it reached a state of absolute repose. But vital forces struggle against a state of repose, which to them means death. They are vital by virtue of their tendency to resist the repose of inert matter; chemical activity disintegrates a stone or other metal, but the decay of organized matter is different in kind; living organisms decompose it and resolve it into its original compounds. Vital connections and mechanical connections differ in kind. You can treat mechanical principles mathematically, but can you treat life mathematically? Will your formulas and equations apply here? You can figure out the eclipses of the sun and moon for centuries to come, but who can figure out the eclipses of nations or the overthrow of parties or the failures of great men? And it is not simply because the problem is so vastly more complex; it is because you are in a world where mathematical principles do not apply. Mechanical forces will determine the place and shape of every particle of inert matter any number of years or centuries hence, but they will not determine the place and condition of matter imbued with the principle of life. We can graft living matter, we can even graft a part of one animal's body into another animal's body, but the mechanical union which we bring about must be changed into vital union to be a success, the spirit of the body has to second our efforts. The same in grafting a tree or anything else: the mechanical union which we effect must become a vital union; and this will not take place without some degree of consanguinity, the live scion must be recognized and adapted by the stock in which we introduce it. Living matter may be symbolized by a stream; it is ever and never the same; life is a constant becoming; our minds and our bodies are never the same at any two moments of time; life is ceaseless change.