You read Merrill? I get six lines into any poem of his & nod off. For Celan & Auden I share your reverence. I think it is in Life Studies, in a poem about Delmore Schwartz, that Lowell calls Freud & Marx the "prophets of joy." I'd better go look this up--I have the feeling I'm misquoting badly. Joy, clearly, is one of the functions of poetry--& as you have noted, certain kinds of philosophy. I'd even go so far as to suggest that philosophy that becomes divorced from the personality of the philosopher is somehow defective, denatured.
Christopher Robinson & Joseph Duemer read Wittgenstein's Philosophical Investigations