Maharishi Patanjali prescribed certain rules of how a person is expected to act in society (Yama) and how personal code and conduct (Niyama) is the expected and essential behavior for individuals to follow. (samatva-yogalaya.com)
Food consumption is controlled in part by the hypothalamus, a portion of the brain that regulates many essential behaviors. (sciencedaily.com)
Gottman cites admiration and fondness as the two most essential behaviors in any relationship. (powerofpositivity.com)