CORRELATIVE TERMS

Correlative terms are also called relative or reciprocal terms, and can be thought of as opposite terms. Mother and child are correlative terms, that is, they are related by immediate inference:

If A is the mother of B, then B is the child of A.

Correlative terms are defined by reference to each other; mother is defined as « woman with children »; child is defined as « son or daughter of a woman ». The following are correlative terms:

cause / effect; double / half; master / slave
action / passion; sell / buy

Generally speaking, two predicates R1 and R2 are in a correlative relation if

A_R1_B <=> B_R2_A
A_Mother_B <=> B_Child_A

« By definition, correlatives are opposites »; they are « ontologically simultaneous » (Hamelin [1905], p. 133). The theme of the correlative is #3 on Aristotle’s list:

Another line of proof is based on correlative ideas (Rhet, II, 23, 3; RR, p. 357).

The topos is illustrated by the enthymemes:

Where it is right to command obedience, it must have been right to obey the command.

If it is no shame for you to sell it, it is no shame for us to buy it (ibid.).

.These conclusions have limits:

If it is legal/tolerated to buy 2 grams of marijuana, then one may sell 2 grams of marijuana.

But what about « possession » and « purchase »?

If it is legal/tolerated to possess 2 grams of marijuana,
then it is legal/tolerated to buy 2g,
then it is legal/tolerated to sell it.

Since the only way for me to get marijuana is to buy it. But the law can distinguish between two kinds of « possession »: possession for personal use is not a crime, but possession for trafficking is.

The following case deals with two pairs of correlatives, knowing/learning and ordering / obeying, articulated by the topos of opposites:

If you want to command, you must first learn to obey (see supra).
The executive, on his way up, had to learn to obey in order to know how to command (quoted in Linguee).