Nozick resists purely psychological or evolutionary accounts of love and argues for a philosophical analysis that captures what lovers themselves experience. To love someone is not merely to care about their well-being or to desire their presence; it is to form a new entity — the we — in which each partner's identity is enlarged and partly constituted by the relationship. Your interests become part of my interests; your well-being becomes partly my well-being; your successes and failures are partly mine. This is not self-abnegation but self-extension: the we is a new subject of experiences, not the dissolution of two subjects into one.
The formation of the we makes love inherently vulnerable in ways that mere care or attachment are not. If the we is part of who I am, then its dissolution — through death, betrayal, or simply the end of the relationship — is not merely a loss of something valuable external to me but a contraction of who I am. Nozick argues that this vulnerability is not a regrettable feature of love that we should try to minimise but an essential expression of love's depth: the willingness to be this vulnerable, to let one's identity be partly hostage to another person's continuation and faithfulness, is the measure of how seriously one has actually formed the we.
For Nozick, love is one of the central ways in which the examined life — the life of philosophical reflection and self-understanding — surpasses merely pleasant or successful life. Love is not merely an emotion or a relationship but a form of knowledge: through loving another person, one gains a kind of understanding of what it is to be a subject in the world — the irreducible first-person perspective, the particular texture of another's experience — that purely theoretical enquiry cannot provide. The examined life includes not only the life of the mind but the life of the heart: the willingness to enter fully into love and to know oneself and the world through that entry.
The account of love and the we appears in the early chapters of The Examined Life (1989). Nozick's analysis has been compared to Robert Solomon's account of love as the fusion of identities, though Nozick distinguishes his view by insisting that the we is a new entity, not a merger of two into one.