Rational animal

The term rational animal (Latin: animal rationale or animal rationabile) refers to a classical definition of humanity or human nature, associated with Aristotelianism.

While the Latin term itself originates in medieval scholasticism, it reflects the Aristotelian view of man as distinguished by a rational principle. In the Nicomachean Ethics I.13, Aristotle states that the human being has a rational principle (Greek: λόγον ἔχον), on top of the nutritive life shared with plants, and the instinctual life shared with other animals, i.e. the ability to carry out rationally formulated projects, That capacity for deliberative imagination was equally singled out as man's defining feature in De anima III.11. While seen by Aristotle as a universal human feature, the definition applied to wise and foolish alike, and did not in any way imply necessarily the making of rational choices, as opposed to the ability to make them.

The Neoplatonic philosopher Porphyry defined man as a "mortal rational animal", and also considered animals to have a (lesser) rationality of their own.

The definition of man as a rational animal was common in scholastical philosophy.Catholic Encyclopedia states that this definition means that "in the system of classification and definition shown in the Arbor Porphyriana, man is a substance, corporeal, living, sentient, and rational".

In Meditation II of Meditations on First Philosophy, Descartes arrives at his famous "I think, I exist" claim. He then goes on to wonder "What am I?" He considers and rejects the scholastic concept of the "rational animal":

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