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I don't have any references for the first coinage of the term Patient. However, in grammars in the Latin tradition it is still customary to find the Latin terms agens and patiens rather than Agent ...
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#1: Initial revision
I don't have any references for the first coinage of the term Patient. However, in grammars in the Latin tradition it is still customary to find the Latin terms _agens_ and _patiens_ rather than Agent and Patient. If those terms are earlier than their English counterparts, this explains it. Latin _patior_ can be glossed as 'to endure, suffer' but just indicates the passive undergoing of some event or action; it is not restricted to illness or misfortune.