If there is nothing of the nature of mosaic composition in the living structure, this fact is one with the fact that there is nothing mechanical in its functioning. It is not actuated from without, as every machine is actuated which is not alive; nor is its functioning, like that of such machines, an assemblage of functions predetermined so far as the machine itself is concerned--predetermined, that is to say, except for intervention from without; unalterable, as unstartable, without external cause. The character of living function is suggested by the word “focalization.” There is a perfectly indivisible concert of function throughout the organism, in every one of its infinite varieties of activity. When the engineer reverses his engine, or otherwise alters its mode of operation, what he really does is to alter the structure of the machinery. The machinery has been specially constructed with a view to unmaking and remaking its nature more or less quickly and conveniently; that is, its parts can be displaced and replaced with reference to each other. Some parts are “thrown out of gear” and shifted back. _And then everything returns to its former state._ Not so in life. The functioning of an organism never remains quite the same in two consecutive instants. There is an incessantly moving emphasis or focus in it. Now one of its potentialities of function is primary or focal, now another. But none can ever cease and then be resumed. In this case, to cease is not to be thrown out of gear, but to die, to perish, to be annihilated. In every phase of the life activity of the organism, all its functions are operative, subsidiary and subservient in varying degrees to that one which for the moment is the focus of all. Thus the organic or vital focus, in its physiological aspect of activity and in its psychological aspect of attention, is never at rest. The modulation is not like the sudden transformations in a kaleidoscope. The evolutions do not take place in the manner suggested by the phrase “Presto, change!” _Modulation_ is the word that describes the process. Or, as Bergson phrases it, the change is continuous, incessant, an _interpenetrating flow_ of processes, in which analysis can make no beginning and no separation; in which analysis, in fact, is absolutely impotent. If the eye is that which sees, the ear that which hears, and so on, it is really the organism entire, and no special, locally differentiated part of it that is the organ. Those so-called parts which, with our false intellectualism, we name the eye or other organ, are, _in their reality_, focal aspects of the entire organism, the organism seen with a certain restriction or limitation of interest.