Ordinarily, when we think about disagreement, we think about disagreeing with others. Interpersonal disagreement is essentially about dissimilarity, but what would it mean for the self to be dissimilar? For Heidegger, care is the structure of Dasein, and the structure of care is the “ahead-of-itself.” For Sartre, the self is separated from its being by the nothingness positioned between the two. Modern existentialism rests on the proposition that we are perpetually other than ourselves, but what is disagreement aside from otherness? This paper draws on Heidegger’s existential analytic of Dasein’s care and Sartre’s writing on negation, especially as it pertains to care, to propose a reconstruction of intrapersonal disagreement that is grounded deeply in the phenomenological ontology of primarily Heidegger and Sartre.