For the sexual passion and love, there are two preferred metaphors: of fire (‘the fire of passion or love’) and water (‘the wave of love’, ‘lovers’ feeling of floating’).
Both of them have concrete reasons. The high temperature of the genitals and of the whole body tells about a fiery passion, while the male seminal emissions and female secretions move the sexuality among watery phenomena.
Those metaphors often lose their primeval meanings, especially when people repeat what they heard about love and sexuality from other people. But there is also a personal experience of metaphors of love and sex, which does not result in uttering words.
We must remind the definition of the metaphor: ‘a figure of speech in which a word or phrase is applied to something to which it is not literally applicable’ (Oxford Dictionary). Even if we do not use words, our love and sexual desires are also assumed through something else like the use of metaphors: a man or a woman in love does not act frankly by direct confessions of love or by getting naked for being ready for the sexual contact. Second, much of our love and sexuality is not ‘literally applicable’, being instead mental experiences.
Before a literal experience of love, the thoughts about it take both a fiery and a watery form. The warming of our body warms the mind, too. Then we hope that love and sexuality will done or accomplish something as an active fire does. When we focus the mind on the possibility of conjoining our body and life with those of another person, the sense of losing ourselves has a watery shape.
Though the fire is the privileged metaphor for love and sexual passion, the watery experience is commoner, since it is felt during the sexual contact through genital fluids which represent its end. Therefore, love and sexuality primarily mean an experience of losing ourselves, not something we continually accomplish. The popularity of the metaphor of fire is in fact the result of our permanent desire to save ourselves from former experiences of losing. When our mind does not adhere to a fiery state again, all of our love and sexual experiences seem irrecoverable losses of our personality on behalf of our past partners.