What the Four Principles Prohibit, and Why

Each of the four regulative principles is tied by ISKCON teaching to one of the four pillars of dharma the tradition holds Kali Yuga progressively erodes: mercy, austerity, cleanliness and truthfulness. Meat, fish and egg eating is prohibited on grounds of nonviolence toward other embodied souls, a position ISKCON grounds in Vaishnava scripture's treatment of all creatures as souls in different bodies rather than in a general South Asian vegetarian custom alone. Intoxication, understood broadly enough to include tea and coffee alongside alcohol, tobacco and drugs, is prohibited as clouding the clarity of mind devotional practice requires.

Gambling is prohibited as an assault on truthfulness and honest livelihood, and illicit sex, defined narrowly as any sexual activity outside marriage or not oriented toward conception, is prohibited as the discipline underlying the other three. Prabhupada presented the four principles as a codification rather than an invention, drawing on ascetic norms already present in the Gaudiya Vaishnava tradition of the Goswamis and the Gaudiya Math, but the specific formulation as an enumerated fourfold list functioning as a bright-line entry standard for initiation is distinctively his own contribution to how the movement organizes lay religious life.