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
Thomas Brown (philosopher) Darwin's theory of transmutation. The philosopher published it in the form of a detailed study "Observations on the zoonomia of Erasmus Darwin" (1798), which was recognized as a mature work of criticism. There, Brown wrote: Noteworthy, Brown's criticism of the Darwinian thesis, like that of Rudolf Virchow, did not come from any religious feeling. Brown's philosophy occupies an intermediate place between the earlier Scottish school and the later associational psychology, to which he really belonged. Later criticism of Brown's philosophy lessened its popularity, a severe attack being made by Sir William Hamilton, 9th Baronet in his "Discussions" and "Lectures on