In romanticism and modernism there is an undercurrent that tries to reach toward the "unthought," or the "inexpressible." This kind of thinking presupposes that language is an imperfect tool; that our received vocabularies and categories are inadequate; that there is an experienced gap between the categories supplied by language and felt reality; and that the inadequacy of our categories need to be signaled even as we use the words we have inherited.
A Celan poem expresses this:
"Should
should a man
should a man come into the world, today, with
the shining beard of the
patriarchs: he could,
if he spoke of this
time, he
could
only babble and babble
over, over
againagain"
(Trans: Michael Hamburger)