Being and Time raises the problem of "authenticity," that is, the potentiality or otherwise for mortal "Dasein" to exist "fully" enough that it might actually understand being. Heidegger is clear throughout the book that nothing makes certain that "Dasein" is capable of this understanding. Finally, this question of the authenticity of individual "Dasein" cannot be separated from the "historicality" of "Dasein". On the one hand, "Dasein", as mortal, is "stretched along" between birth and death, and thrown into its world, that is, thrown into its "possibilities", possibilities which "Dasein" is charged with the task of assuming. On the other hand, "Dasein's" access to
Being and Nothingness has been traditional with non-existential philosophers" and thereby remaining a Cartesian rationalist. Susan Sontag, writing in an essay in "The Supplement" to the "Columbia Spectator" that was later published in "Against Interpretation" (1966), praised Sartre's discussions of the body and concrete relations with others, identifying them as part of a French tradition of serious thought about problems of fundamental importance. John B. Vickery wrote that Sartre's work resembles Sir James George Frazer's "The Golden Bough" (1890) in the way its author "merges psychology and the concrete sense of fiction", although he considered it less readable than Frazer's work. The philosopher