The author is driving home the point that

Directions: Read the following passage and answer the question.
And yet “Know thyself” has always been considered supremely excellent advice, as true for our time, as for the age of Socrates. It certainly is disregarded by most of us, as fully as it was by many of the Greeks, whom Socrates interrogated so ruthlessly. Is there then a sort of self-analysis, which can be carried out for its own sake, and which can be, at the same time, of vital use? It is time to ask these questions if we are ever to know how to analyze ourselves with profit, if we are ever to know ourselves. As students, we are content with every other knowledge but this. After all the self probing of the religious and philosophical, during long centuries, what have we learned? Truly to ourselves, we are enigmas. To know everything else except the self that knows, what a strange position! The one thing that we do not know -- that we feel as if we never could know, is the Self in us. What can we do? And what can we not do? What is the reason of this faculty, or that want of faculty? We have never reached an understanding of ourselves, which makes us not only know, but perceive what we are capable of knowing; which makes us aware, not only that we can do something, but why we can do it. If we would but take half the trouble to understand ourselves that we take to study a science or art, we might then cultivate some our own special lines of thought, our own gifts, that portion of individuality, which we each possess.