By Schubert Ogden
To be an understanding (or, alternatively, thinking-speaking) animal is one thing; to be a rational animal, something else. To be an understanding animal is to have the use of abstract concepts or universals, such use being indicated behaviorally by the use of language and other kinds of symbols. To be a rational animal is to think and to act rationally, in accordance with the dictates of reason, theoretical as well as practical.
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