Freud begins by summarizing his claims thus far in the essay. The psyche is comprised of the id, ego, and superego. Perceptions are a key factor for the ego just as instincts are a key factor for the id. He then adds to this argument that the ego is also “subject to the influence of the instincts” (30) like the id, as the ego is a “modified part” of the id.

Freud then reprises his discussion about the two classes of instincts he first introduced in the final chapter of Beyond the Pleasure Principle (1920). The first instinct is one that is a dominant focus of psychology, the sexual instincts or Eros. The sexual instinct is connected to erotic desire but also connected to self-preservation. The second instinct is the death instinct, or the drive to return to an inanimate state. These two instincts are in conflict and compromise with each other. He argues that single-celled organisms have a death instinct that is diverted to the external world through the body.

Freud builds on this concept by discussing how these two instincts can work in tandem. For example, he argues, the death instinct often serves the sexual instinct. He hypothesizes that this is what causes epilepsy. He describes how the “polarity of love and hate” (32) are emblematic of the opposition between the sexual and death instincts. Drawing from his clinical experience, he argues that love and hate often appear in sequence, either love turning into hate or hate turning into love, and that this dynamic is illustrative of how the two instincts are correlated.

For example, when someone feels desire for another person and is rejected, the object of love can become the focus of intense hatred. Freud argues that the transition from love to hate in this instance and others is not the result of the other person’s behavior but rather because of the subject’s internal psyche. Similarly, hatred for a rival can transform into desire. Freud argues that this dynamic occurs because the sense of rivalry cannot be satisfied and is therefore turned into love.

Freud states that his arguments about instinct rest on the assumption that there is a form of “neutral” psychic energy that can be transformed and displaced. He hypothesizes that this energy is “desexualized Eros,” or narcissistic libido formed when an object-cathexis is internalized and imprinted on the ego. This energy follows the rules of the pleasure principle: that a psyche will seek to go towards pleasure and away from displeasure. It fulfills this principle by removing barriers to pleasure and ridding itself of unpleasant psychic sensations, for example alleviating repressed anger by punishing or enacting revenge on those who have harmed the psyche. This drive can lead to injustice: for example, the punishment of a scapegoat when those actually responsible for the wrongdoing cannot be identified or punished. This desexualized erotic energy is sublimated, likely by the mediation of the ego, as the ego transforms itself into the object of desire.

Freud concludes that the “clamour of life” (36) is largely driven by Eros, while the death instinct is largely “mute.” Eros creates new instincts, to which the id responds in accordance with the pleasure principle in order to release tension in accordance with the death drive. Freud compares this cycle to the cycle of sexual arousal and orgasm, noting that some creatures literally die in the act of copulation.