The first was what may be called the hope which lies in the imperfection of man.

The characteristic poem of "Old Pictures in Florence" expresses very quaintly and beautifully the idea that some hope may always be based on deficiency itself; in other words, that in so far as man is a one-legged or a one-eyed creature, there is something about his appearance which indicates that he should have another leg and another eye.

The poem suggests admirably that such a sense of incompleteness may easily be a great advance upon a sense of completeness, that the part may easily and obviously be greater than the whole.

And from this Browning draws, as he is fully justified in drawing, a definite hope for immortality and the larger scale of life.

For nothing is more certain than that though this world is the only world that we have known, or of which we could even dream, the fact does remain that we have named it "a strange world." In other words, we have certainly felt that this world did not explain itself, that something in its complete and patent picture has been omitted.
And Browning was right in saying that in a cosmos where incompleteness implies completeness, life implies immortality.