what does the genie mean when he says "to give a thing a name, a lable, a handle, to rescue it from anonymity to pick out of the place of namelessness, in short to identify it-well that's a way of brining the said thing into being"

The appearance of Iff the Water Genie is another allusion to One Thousand and One Arabian Night. One of the most famous tales in that work is “Aladdin’s Wonderful Lamp,” in which a young boy is given a ring with a genie inside that does the bidding of those that command it. In the same way, Iff is forced to do the bidding of Haroun because Haroun holds his magic wrench. The Genie tells Haroun that he should not merely believe with his eyes; there are more things on Heaven and Earth that can't be seen simply by looking.