“Health and cheerfulness mutually beget each other.”

“White prejudice and discrimination keep the Negro low in standards of living, health, education, manners and morals. This, in its turn, gives support to white prejudice. White prejudice and Negro standards thus mutually ‘cause’ each other.”

“faith and reason “mutually support each other”; each influences the other, as they offer to each other a purifying critique and a stimulus to pursue the search for deeper understanding”

“Women's mutual understanding comes from the fact that they identify themselves with each other; but for the same reason each is against the others.”

“If men and women are to understand each other, to enter into each other's nature with mutual sympathy, and to become capable of genuine comradeship, the foundation must be laid in youth.”

“The total possible consciousness may be split into parts which co-exist but mutually ignore each other.”

“Marriage… is the union of two people of different sexes with a view to the mutual possession of each other's sexual attributes for the duration of their lives.”

“We knew each other. We talked. We passed each other going to the set of our own films. We were doing our jobs. We had great mutual respect.”

“Maybe if you weren’t busy throwing rocks at each other, you could spend a little time on the other niceties of life, such as cooperation and mutual advancement.”

“Coadaptation is the process whereby systems of related agents take mutual advantage of each other in order to change more effectively, yet still be adaptive in each agent's particular situation.”