I know my soul hath power to know all things

I know my soul hath power to know all things, Yet she is blind and ignorant in all: I know I'm one of Nature's little kings, Yet to the least and vilest things am thrall. I know my life's a pain and but a span; I know my sense is mock'd in ev'rything; And, to conclude, I know myself a Man, Which is a proud and yet a wretched thing.