Ambivalence (as in practical conflicts, moral dilemmas, conflicting beliefs, and mixed feelings) is a central phenomenon of human life. Yet ambivalence is incompatible with entrenched philosophical conceptions of personhood, judgement, and action, and is denied or marginalised by thinkers of diverse concerns. This book takes a radical new stance, bringing the study of core philosophical issues together with that of ambivalence. The book proposes new accounts in several areas - including subjectivity, consciousness, rationality, and value - while elucidating a wide range of phenomena expressive of ambivalence, from emotional ambivalence to self-deception. The book rejects the view that ambivalence makes a person divided, showing that our tension-fraught attitudes are profoundly unitary. Ambivalence is not tantamount to confusion or to paralysis: it is always basically rational, and often creative, active, and perceptive as well. The book develops themes from Wittgenstein, Davidson, Sartre, and Freud. It engages with contemporary debates in Analytic Philosophy in addition to work ranging from Aristotle to Cultural Studies and Empirical Psychology, and considers a rich set of examples from daily life and literature.