whistle what you would normally entrust to words

Not a blackbird, more like a swallow or perhaps a sand-martin.

[First off, go to Birdsong DAB radio channel, running 24 hours a day (click on the player at the bottom of the entry to listen to the live broadcast) to set the tone for the following post. The bird recordings were originally used as a test transmission on Classic FM prior to its launch and listeners currently enjoy the soundtrack again since the radio station Oneword ceased to broadcast on the 11th of January 2008 and the recording was used again as a substitute. Listeners are warned that the bird song could cease to be broadcast without warning at any time.]

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'After a while the whistle is repeated - by the same blackbird or by its mate - but always as if this were the first time it had occurred to him to whistle; if this is a dilaogue, each remark is uttered after long reflection. But is it a dialogue, or does each blackbird whistle for itself and not for the other? And, in whichever case, are these questions and answers (to the whistler or to the mate) or are they confirmations of something that is always the same thing (the bird's own presence, his belonging to this species, this sex, this territory)? Perhaps the value of this single word lies in its being repeated by another whistling beak, in it not being forgotten during the interval of silence.

Or else the whole dialogue consists of one saying to the other "I am here," and the lengths of the pauses adds to the phrase the sense of a "still," as if to say: "I am still here, it is still I." And what if it is in the pause and not in the whistle that the meaning of the message is contained? If it were in the silence that the blackbirds speak to each other? (In this case the whistle would be a punctuation mark, a formula like "over and out.") A silence, apparently the same as another silence, could express a hundred different notions; a whistle could too, for that matter; to speak to one another by remaining silent, or by whistling, is always possible; the problem is understanding one another. Or perhaps no one can understand anyone: each blackbird believes that he has put into his whistle a meaning fundamental for him, but only he understands it; the other gives him a reply that has no connection with what he said; it is a dialogue between the deaf, a conversation without head or tail.'

Mr Palomar (Palomar's Vacation: Palomar in the Garden: The Blackbird's Whistle), Italo Calvino.