Evolutionary psychologists have theorized that taboos against female promiscuity evolved on the basis of paternity anxiety.

Some evolutionary psychologists theorize that guilt and shame helped maintain beneficial relationships, such as reciprocal altruism.

Some psychologists have theorized that the formation of youth culture is an attempt to adopt an identity that reconciles these two conflicting expectations.

All three Abrahamic religions were founded by men, so some scholars and psychologists have theorized that they may dramatize important themes around men's relationship with their fathers for the western world.

Journalists, criminal psychologists and astrologers theorized about a gunman who disappeared as quietly as he had appeared.

Evolutionary psychologists have theorized that these specialized modules enabled our ancestors to react quickly and effectively to environmental challenges.

Many psychologists have theorized that the development of the visual area of the brain in animals is closely related to intelligence.

Amateur and professional psychologists alike have theorized about it.

Environmental psychologists have theorized that density and crowding can also have an adverse effect on mood and may cause stress-related illness.

The synergistic psychologists theorized that for some unknown reason matrix-talents had enormous difficulty coming to terms with the paranormal side of their natures.