Children are the living messages we send to a time we will not see.

Neil Postman (1931-2003) American author, media theorist, cultural critic

The Disappearance of Childhood, Introduction (1982)
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Often misattributed to John W Whitehead (b. 1946) American lawyer, conservative activist, author. The same line appears, unattributed, in Whitehead's The Stealing of America, ch. 10 (1983); elsewhere in there Whitehead references Postman's book, so it is likely he took the line from Postman.For more discussion of this, see Lance Strate's Blog Time Passing: Children are the Living Messages We Send to a Time We Will Not See.