Sartre begins the journey of understanding consciousness by attempting to determine the connection between being-for-itself and being-in-itself. He argues that they cannot be considered independently of one another. Doing so would turn consciousness into an abstraction that could never be fully understood, because existence is inherently concrete. Instead of looking at the subject abstractly, he proposes two concrete questions: What does it mean to be in this world, and what are man and world that makes the relationship between the two possible? Sartre suggests that the answer to these questions, like all inquiries, may have a negative quality, such as “nothing” and “nobody.” The philosopher cautions against overlooking non-beings and the role they play in existence. He offers three examples of non-beings: knowledge of man, transcendence, and limitation. All questions are subject to these three non-beings, or negations. The fact that questions are often exchanged between people means that the three non-beings that Sartre outlines may inhibit the ability of humans to ever truly unlock the answer.

This portion of the text provides the latter component of the book’s title—nothingness. Sartre suggests that the human condition is surrounded by and contains nothing. Just as being is an inherent part of existence, nothingness pervades everything.