In book 4 we see Satan express doubt as he walks through the Garden of Eden. He says that Hell is within himself instead of being a physical place. Compared to the first books, this is a change in character for Satan. he wants to be forgiven but knows that it would be a lie. He says
“Upon himself; horror and doubt distract
His troubl’d thoughts, and from the bottom stirr
The Hell within him, for within him Hell
He brings, and round about him, nor from Hell
One step no more then from himself can fly
By change of place: Now conscience wakes despair
That slumberd, wakes the bitter memorie
Of what he was, what is, and what must be
Worse; of worse deeds worse sufferings must ensue.” (Milton, 4, 18-25).
What could have caused this? Obviously, there are reasons. But today we see these figures as all-knowing and powerful, so the images of Satan doubting himself and not being confident is an interesting view of a usually intimidating figure. Why did Milton decide to paint him like this?