... The one primary word is the combination I-Thou. The other primary word is the combination I-It ... If I face a human being as my Thou, and say the primary word I-Thou to him, he is not a thing among things, and does not consist of things ...
When Thou is spoken, the speaker has no thing for his object. For where there is a thing there is another thing. Every It is bounded by others; It exists only through being bounded by others. But when Thou is spoken, there is no thing. Thou has no bounds ...
These are the two basic privileges of the world of It. They move man to look on the world of It as the world in which he has to live, and in which it is comfortable to live, as the world, indeed, which offers him all manner of incitements and excitements, activity and knowledge. In this chronicle of solid benefits the moments of the Thou appear as strange lyric and dramatic episodes, seductive and magical, but tearing us away to dangerous extremes, loosening the well-tried context, leaving more questions than satisfaction behind them, shattering security — in short, uncanny moments we can well dispense with. For since we are bound to leave them and go back into the “world,” why not remain in it? Why not call to order what is over against us, and send it packing into the realm of objects? Why, if we find ourselves on occasion with no choice but to say Thou to father, wife, or comrade, not say Thou and mean It? To utter the sound Thou with the vocal organs is by no means the same as saying the uncanny primary word; more, it is harmless to whisper with the soul an amorous Thou, so long as nothing else in a serious way is meant but experience and make use of ...
http://www.bopsecrets.org/gateway/passages/buber.htm