II
The most obvious fact about self-development is that it is a species of change, and that change is associated with sadness. Heraclitus, the weeping philosopher of the Greeks, discovered this fact five hundred years before Christ. "Nothing abides," he said, "all is fleeting." We stand in a moving tide, unable to bathe twice in the same stream; before we can stoop a second time the flood is gone. In every age this is the common theme of lamentation for poet, moralist, common man and woman. All other causes of sadness are secondary to it. As soon as we have comprehended anything, have fitted it to our lives and learned to love it, it is gone.
Such is the aspect which change ordinarily presents. It is tied up with grief. We regard what is precious as stable; and yet we are obliged to confess that nothing on earth is stable—nothing among physical things, and just as little among mental and spiritual things. But there are many kinds of change. We are apt to confuse them with one another, and in so doing to carry over to the nobler sorts thoughts applicable only to the lower. In beginning, then, the discussion of self-development, I think it will conduce to clearness if I offer a conspectus of all imaginable changes. I will set them in groups and show their different kinds, exhibiting first those which are most elementary, then those more complex, and finally those so dark and important that they pass over into a region of mystery and paradox.