Devise a strategy for proving that if 'P implies Q' is true, then 'not Q implies not P' must also be true.
user
{"source": "argilla/distilabel-reasoning-prompts", "kind": "synthetic", "evolved_from": null}
Devise a strategy for proving that if 'P implies Q' is true, then 'not Q implies not P' must also be true.
user
DUMMY RESPONSE
assistant