Article 2. Whether justice is always towards one another?

Tully says (De Officiis i, 7) that "the object of justice is to keep men together in society and mutual intercourse." Now this implies relationship of one man to another. Therefore justice is concerned only about our dealings with others. 

I answer that, As stated above (Question 57, Article 1) since justice by its name implies equality, it denotes essentially relation to another, for a thing is equal, not to itself, but to another. And forasmuch as it belongs to justice to rectify human acts, as stated above (57, 1; I-II, 113, 1) this otherness which justice demands must needs be between beings capable of action. Now actions belong to supposits [Cf. I, 29, 2] and wholes and, properly speaking, not to parts and forms or powers, for we do not say properly that the hand strikes, but a man with his hand, nor that heat makes a thing hot, but fire by heat, although such expressions may be employed metaphorically. Hence, justice properly speaking demands a distinction of supposits, and consequently is only in one man towards another. Nevertheless in one and the same man we may speak metaphorically of his various principles of action such as the reason, the irascible, and the concupiscible, as though they were so many agents: so that metaphorically in one and the same man there is said to be justice in so far as the reason commands the irascible and concupiscible, and these obey reason; and in general in so far as to each part of man is ascribed what is becoming to it. Hence the Philosopher (Ethic. v, 11) calls this "metaphorical justice."

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