I would single out "War and the Philosophy of the Sacred, "Poetry and the Temptation of the End of the World," and "Surrealism and God," but those on Jacques Prévert, (From the Stone Age to Jacques Prévert), René Char (René Char and the Force of Poetry), Camus' (The Rebel (The Age of Revolt), and his critique of Blanchot on Sade (Happiness, Eroticism and Literature) represent aesthetic critical thinking above and beyond.
Begin with the impossible. And never back off.
If you want to think about, to write about "literature" (I am more and more estranged from this word... let's go back in time and call it all poetry... and what doesn't come up to poetry (or merely aspires to it without overwriting all earlier attempts to define it, is merely "literature." What we called the glossy hand-outs at the auto show when I was a kid in the 50's).
"...poetry is...literature which is no longer literary, which escapes from the rut in which literature is generally entrapped. For us, 'poetic' cannot have a set value in the same way as an Anjou wine or a fabric (Hear that, Mr. Wood!) (p. 138) ... if you want to think about poetry, there's no where else to begin.
... but with the impossible.
You have volunteered to be shackled to two draft horses. They are pulling, one to the north, one to the south. Your job, if you choose to accept it, is to never give way to one side or the other, even as they tear you, body and soul, asunder.