I next proposed a triangular theory of love, which holds that love can be understood in terms of three components that together can be viewed as forming the vertices of a triangle. The triangle is used as a metaphor, rather than as a strict geometric model.
These three components are intimacy (top vertex of the triangle), passion (left-hand vertex of the triangle), and decision/commitment (right-hand vertex of the triangle).
Intimacy refers to feelings of closeness, connectedness, and bondedness in loving relationships.
Passion refers to the drives that lead to physical attraction and excitement.
Decision/commitment refers, in the short-term, to the decision that one loves a certain other, and in the long-term, to one’s commitment to maintain that love.
More of each component leads to different sizes of love triangles, and different balances of the three components give rise to different shapes of triangles.