Converses

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Two predicates are converses if they describe the same relation from opposing perspectives.

For any pair of predicates P, Q
P and Q are converses iff
for all x, y,
P(x,y) ↔ Q(y,x)

Examples

  • 'above' vs. 'below'
  • 'in front of' vs. 'behind'
  • 'before' vs. 'after'
  • 'parent of' vs. 'child of'
  • 'huest' vs. 'host'
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