I&I

From a post on a rastafari web forum, the definition of I&I is as follows

"When I&I say, One love, we mean that there is only one love. The love between man & Ja, between man & man, between man & Iman, between man & woman, between man and all creatures of Ja, is but one and the same love. One cannot love part of Ja any more than he can love only some men and not others. Ja is all men and all men are Ja. Shalom Aleichem my brethern. Peace be with you."

The simple statement I&I is a statement that all people are one, hence, "One Love".