Rather than adopting a view of Fichte as a “proto-existentialist,” as some scholars have suggested, I instead aim to develop an account which articulates a fundamental existential structure which helps to elucidate and situate later notions of existential subjectivity by accounting for its condition of possibility. In this vein, existentialism not only articulates a certain kind of being in the world but a logical condition of the structure of subjectivity itself. I call this structuring condition existential logic, and locate it in Fichte's Wissenschaftslehre. I develop the term existential logic instead of merely attributing to Fichte the term existential-ism or existentialist, insofar as I aim to locate an operative structure within the being who then becomes an existential subject for whom existential engagement is only then possible. The term existential logic suggests that the striving of the self both with and against the world—as existential phenomenology would have it—is a structure inherent within Fichte's logical deduction and formulation of the Absolute I.