“The more narrowly we examine actual language, the sharper becomes the conflict between it and our requirement.  (For the crystalline purity of logic was, of course, not a result of investigation: it was a requirement.)  The conflict becomes intolerable; the requirement is now in danger of becoming empty.—We have got on to slippery ice where there is no friction and so in a certain sense the conditions are ideal, but also, just because of that, we are unable to walk.  We want to walk: so we need friction.  Back to the rough ground!”

Ludwig Wittgenstein
Philosophical Investigations, #107