Thanks for the striking Ben Jonson fragment, Robert. Now that IS pre-Keatsian--though, as you say, very different in tone, more sober than sensual, more calculating than impetuous. Reading the poem again, I feel more the sobriety of the last 30-odd lines. From "I gave rein to the conceit" to the ambiguous "None can well behold with eyes," there's also an emphasis on the quality of delusion in the conceit, a sense of being carried off into a starry nowhere. What are we to make of "None can well behold with eyes"? It seems to mean that in metaphor, or conceit, we lose the faculty of sight, perhaps insight as well--we lose our grounding in the actual, the palpable. Yet the countercurrent remains: that metaphor amplifies and enriches what we see with what we lushly imagine.