Text: I am to take it then that you decline to say where you were at the time that Mr. Mace positively recognized you as entering the shop to purchase strychnine?
Entailment: So, even though Mr. Mace positively places you at his shop buying strychnine, you refuse to provide an alibi of where you actually were at that time?
Contradiction: So your alibi is that you were checking on the outdoor sheepdog at Styles?