It is no bad thing that these contradictory tendencies should subsist, for this variety in the conception of phenomena gives to actual science a character of intense life and of veritable youth, capable of impassioned efforts towards the truth.

Spectators who see such moving and varied pictures passing before them, experience the feeling that there no longer exist systems fixed in an immobility which seems that of death.

They feel that nothing is unchangeable; that ceaseless transformations are taking place before their eyes; and that this continuous evolution and perpetual change are the necessary conditions of progress.
A great number of seekers, moreover, show themselves on their own account perfectly eclectic.

They adopt, according to their needs, such or such a manner of looking at nature, and do not hesitate to utilize very different images when they appear to them useful and convenient.
And, without doubt, they are not wrong, since these images are only symbols convenient for language.

They allow facts to be grouped and associated, but only present a fairly distant resemblance with the objective reality.