Even before the exact answer was reached, Crick crystallized its fundamental principles in a statement that he called {and is called to this day} the Central Dogma. It is a hypothesis about the direction of evolution and the origin of life; it is provable in terms of Shannon entropy in the possible chemical alphabets: Once "information" has passed into protein it cannot get out again. In more detail, the transfer of information from nucleic acid to nucleic acid, or from nucleic acid to protein may be possible, but transfer from protein to protein, or from protein to nucleic acid is impossible. Information means here the precise determination of sequence.
( James Gleick )
[ The Information: A History, a ]
www.QuoteSweet.com