Kissing is a means of getting two people so close together that they can't see anything wrong with each other.
Kissing is a form of loss and partial compensation like imaginative vision which compensates for blindness, castration and loss.
Kissing is regarded (as reported in 1886) as preliminary to, or co-existant with, sexual intercourse.
Kissing is a chemical choir, involving a host of chemicals (oxytocin, dopamine, saratonin), all interacting together to make us feel a certain way.
Kissing is a pleasure derived from close contact with a beloved person which is replaced in various parts of the world by the rubbing of noses, by the rubbing or patting of the arms, breasts, or stomachs, or by one man striking his own face with the hands or feet of another.
Kissing is a biological litmus test through which the body tries to figure out how compatible one is with their partner.
Kissing is a perversion in that the parts of the body involved do not form part of the sexual apparatus but constitute the entrance to the digestive tract.