From the Heidegger entry in a philosophical encyclopedia.
Even though Heidegger does not explicitly address the erotic dimension of sexuality, he does provide the phenomenological framework for doing so. Through its embodiment, human existence participates in the dynamic process whereby things come into presence only by retaining an affinity with absence. This negativity entails that hiddenness is necessarily part of the veil through which we encounter ourselves and others. Human existence as care harbors an erotic dimension, since in the movement into disclosedness and unhiddenness the self endures the tension of confronting the retreat back into concealment and hiddenness, the allure of mystery that pervades any appearance of beauty. Thus, phenomenologically speaking, the erotic does not lie purely in nakedness but in that dimension of withholding and withdrawal that necessarily accompanies the unveiling of nudity (for example, in the presence of the other). Eroticism, then, thrives by giving play (Spiel) to the dynamic of revealing/concealing, in the offering and taking hack of nudity that occurs, say, when the curves of a woman’s legs momentarily appear while walking in a split skirt. Sexual intimacy Consists of a kind of play that invites variation and exalts in the introduction of new possibilities, the hallmark of imagination and fantasy (as in role-playing). For Heidegger, a fetishistic attachment to certain clothing could be explained by a phenomenological appeal to the enactment of play and fantasy, rather than by a psychoanalytic reference to infantile desires and fixations.
In his brief allusions to eroticism. Heidegger does not explicitly link sex and love. As his discussions in Schelling's Treatise on the Essence of Human Freedom and Zollikon Seminars attest, love is an enactment of care, a way of cultivating openness. It is an activity of “letting be,” of allowing the uniqueness of beings, including other people, to be come unconcealed and stand forth in the singularity of their manifestation. The self’s participation in this openness is an essential condition of intimacy or an authentic response to the other, as when one heeds the “voice of [a] friend”. One’s uniqueness as an individual and potential for intimacy—the exercise of care toward oneself and others—gives way to the diversity of sexual practices. Heidegger thereby allows for the possibility of different sexual orientations, although he does not explicitly address their occurrence. By the same token, Heidegger’s tacit acceptance of sexual experimentation would seem to promote an open climate of sexual involvement with multiple partners. (See Frederick Elliston’s [1944—1987] Heideggerian defense of promiscuity.) In Being and Time, however, we can find textual support for the opposite position, insofar as Heidegger defines freedom as the selection of one possibility to the exclusion of others. He thereby implies that monogamy or an intimate relation with only one significant other might be a preferred avenue by which the self can realize its individuality.
Despite the brevity of Heidegger’s discussion of sex, his analysis of authentic existence profoundly influenced the treatment of sexuality undertaken by the two most prominent founders of existential psychotherapy, Ludwig Binswangcr(1881—1966) and Medard Boss (1903—1990). Both considered more broadly than Heidegger did the spectrum of sexual behavior as it contributes to or detracts from the individual’s quest for self-actualization. Heidegger’s circumvention of sexuality also provided the opportunity and point of departure for the French thinkers Sartre. Jacques Derrida (1940—2004), and Luce Irigaray to develop philosophies designed to confront the multifaceted character of eroticism. Heidegger’s succinct discussion of sexuality, in terms of its insights and omissions, provides an important cornerstone for addressing eroticism from a phenomenological perspective.