subcontrary

A subcontrary opinion can still find common ground.

Definition

1. Noun (Logic):

   • A proposition that is related to another in such a way that both cannot be false at the same time, though both may be true. In traditional logic, subcontraries are pairs of particular statements (e.g., "Some S are P" and "Some S are not P") that are opposed but not contradictory.

2. Adjective:

   • Slightly contrary: Having a mild or partial opposition; not fully contradictory but somewhat opposed.
   • Relating to a subcontrary proposition: Pertaining to the logical relationship between two subcontrary statements.

Usage Examples

• Noun:

  • In the square of opposition, "Some men are honest" and "Some men are not honest" are subcontraries. (These two statements cannot both be false; at least one must be true.)

• Adjective:

  • Her opinion was subcontrary to his, differing in detail but not in principle. (Her view was slightly opposed, not completely contradictory.)

Advanced Usage

• "subcontrary opposition": A logical relationship where two particular propositions can both be true but cannot both be false.
  • The subcontrary opposition between "Some birds can fly" and "Some birds cannot fly" is valid. (Both statements are true, but neither can be entirely false.)

Variants and Related Words

• Subcontrariety (n): The state or quality of being subcontrary.
  • The subcontrariety of these two statements was recognized by logicians. (The quality of being subcontrary.)

Synonyms

• Partially opposed: In mild disagreement.
• Semi-contradictory: Not fully contradictory but somewhat opposed.

Related Idioms