Bebe's Precious Pups
The character of the boxer is of the greatest importance and demands the most solicitous attention. He is renowned from olden times for his great love and faithfulness to his master and household. He is harmless in the family, but distrustful of strangers, bright and friendly of temperament at play, but brave and determined when aroused. His intelligence and willing tractability, his modesty and cleanliness make him highly desirable family dog and cheerful companion. He is the soul of loyalty and honesty, and is never false or treacherous even in his old age.
--1938 AKC Boxer Breed Standard.