We are difficult. Human beings are difficult. We're difficult to ourselves, we're difficult to each other. And we are mysteries to ourselves, we are mysteries to each other. One encounters in any ordinary day far more real difficulty than one confronts in the most "intellectual" piece of work. Why is it believed that poetry, prose, painting, music should be less than we are? 2 With these words, part of an interview published in the Paris Review in 2000, Geoffrey Hill responds to the interviewer's comment that his poetry is often thought to be inaccessible by presenting this abstruseness as a natural and appropriate response to the challenges of understanding humanity itself. In particular, Hill touches on two themes which, this essay argues, were of profound concern to writers and theologians in the later sixteenth and early seventeenth centuries: the opacity of the self to the self, and the capacity of poetics to explore this mystery. In the Western world, philosophy has long been conceived of as a discipline of self-knowledge, and the Socratic, ethical, and spiritual imperative to 'know thyself' was frequently reiterated in the early modern period. Nonetheless, thinkers from across the confessional spectrum frequently emphasized the difficulties (and sometimes even the impossibility) of achieving self-knowledge. 'Thou art to narrow, wretch', Donne informs his soul in The Second Anniversary (1612), 'to comprehend / Euen thy self'. 3 This notion that self-knowledge is-counter-intuitively-the most difficult form of knowledge owed something to two related phenomena which emerged around the middle of the sixteenth century: the development of the anthropological assumptions of Reformed theology, and the revival of classical scepticism. Montaigne's long essay 'An Apologie of Raymond Sebond', first published in the 1580 edition of his Essays, and translated into English by John Florio in 1603, is seminal here. 4 An 1 Research leading to this essay received funding from the European Research Council under the European Union's Seventh Framework Programme (FP7/2007-2013)/ERC grant agreement no 617849. Many thanks to Shani Bans, Joan Pong Linton, Rachel Willie, and the editors of this volume for helpful comments on drafts of this essay. 2 'The Art of Poetry LXXX: Geoffrey Hill', an interview with Carl Phillips, p. 275.