From this site: http://www.angelfire.com/md2/timewarp/sartre.html we read: What is Being? What is Nothingness? How are they related? For Sartre, Being is objective, it is what is. Being is in-itself. Existence, on the other hand, has a subjective quality in relation to human reality. Existence refers to the fact that some individual or thing is present in the world. But...(here I assume the site is correct about Sartre)...what does Sartre gain by holding on to 'being' since he also rejects, in the introduction to Being and Nothingness, Kant’s concept of noumenon ? So my question, what the difference between the "in-itself" of Sartre "being" and the "in-itself" of Kant noumenon ? If no difference, is philosophy of Sartre then falsified ? Finally, for Descarte and his "I think therefore I am", is the "I am" of Descarte the "being" or the "existence" of Sartre (or both or neither?) ? Any thought on either of these two questions is appreciated.