The sentence you object to was not thought of as a teleological dogma of what humanity is meant to do or not, but an evolutionary perspective of why our brains are not very well equipped to handle some questions and/or scales of such dimensions (maybe it wasn't the most apt expression -- I am not a native English speaker). The sensory and processing equipment that has evolved by giving early hominids the advantage to use tools and language stumbles somehow when it is confronted with the vastness of the universe -- it loses track of the local reference frame...