"Let us, in our character of knowers, not be ungrateful towar..." — Friedrich Nietzsche quote meaning

Let us, in our character of knowers, not be ungrateful towards such determined reversals of the ordinary perspectives and values, with which the mind had for too long raged against itself with an apparently futile sacrilege! In the same way the very seeing of another vista, the very wishing to see another vista, is no little training and preparation of the intellect for its eternal "Objectivity" — objectivity being understood not as "contemplation without interest" (for that is inconceivable and nonsensical), but as the ability to have the pros and cons in one's power and to switch them on and off, so as to get to know how to utilise, for the advancement of knowledge, the difference in the perspective and in the emotional interpretations. But let us, forsooth, my philosophic colleagues, henceforward guard ourselves more carefully against this mythology of dangerous ancient ideas, which has set up a "pure, will-less, painless, timeless subject of knowledge"; let us guard ourselves from the tentacles of such contradictory ideas as "pure reason," "absolute spirituality," "knowledge-in-itself": — in these theories an eye that cannot be thought of is required to think, an eye which ex hypothesi has no direction at all, an eye in which the active and interpreting functions are cramped, are absent; those functions, I say, by means of which "abstract" seeing first became seeing something; in these theories consequently the absurd and the nonsensical is always demanded of the eye. There is only a seeing from a perspective, only a "knowing" from a perspective, and the more emotions we express over a thing, the more eyes, different eyes, we train on the same thing, the more complete will be our "idea" of that thing, our "objectivity." But the elimination of the will altogether, the switching off of the emotions all and sundry, granted that we could do so, what! would not that be called intellectual castration?