Another rendering by Bailey that has always bothered me is this one at Book 2:37:
But if we see that these thoughts are mere mirth and mockery, and in very truth the fears of men and the cares that dog them fear not the clash of arms nor the weapons of war, but pass boldly among kings and lords of the world, nor dread the glitter that comes from gold nor the bright sheen of the purple robe, can you doubt that all such power belongs to reason alone, above all when the whole of life is but a struggle in darkness?
I don't find this one as objectionable as my first example, but the phrase "belongs to reason alone" is easy to misinterpret if someone isn't aware of Epicurus' views on logic and the priority of the senses, and "when the whole of life is but a struggle in darkness" is easy to read in a negative way that Lucretis is implying that the whole of life IS and HAS TO REMAIN a struggle in darkness.
Munro does better with his "withal" to indicate that the whole of life does not have to be a struggle in the dark:
how can you doubt that this is wholly the prerogative of reason, when the whole of life withal is a struggle in the dark?
And Dunster doesn't make it so easy to misinterpret the Epicurean position on reason by saying "want of sense":
Do you doubt but all this stuff is want of sense, and all our life is groping in the dark?
So here I would combine Dunster and Munro to improve that final statement.