Something might be true while being harmful and dangerous in the highest degree. Indeed, it might be a basic characteristic of existence that those who know it completely would perish, in which case the strength of a spirit should be measured according to how much of the 'truth' one could still barely endure- or to put it more clearly, to what degree one would require it to be thinned down, shrouded, sweetened, blunted, falsified.
Friedrich Nietzsche (2009). “Basic Writings of Nietzsche”, p.239, Modern Library