If nature has made any one thing less susceptible, than all others, of exclusive property, it is the action of the thinking power called an Idea; which an individual may exclusively possess as long as he keeps it to himself; but the moment it is divulged, it forces itself into the possession of every one, and the reciever cannot dispossess himself of it. it’s peculiar character too is that no one possesses the less, because every other possesses the whole of it. He who recieves an idea from me, recieves instruction himself, without lessening mine; as he who lights his taper at mine, recieves light without darkening me.

Thomas Jefferson (1743-1826) American political philosopher, polymath, statesman, US President (1801-09)

Letter to Isaac McPherson (13 Aug 1813)
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