Meet John. Who knows what sort of man he was before he lost his eyesight? He does not say. Now he is a quiet, unassuming man of heroic character. You could be in a room with him and not notice him. But I guarantee he will have noticed you. His eyes may be gone, but his other senses have more than made up for their loss. He is extremely perceptive -- which most people do not know simply because he does not tell them.
And if I may, I will devulge a little bit of my own philosophy on this with a question: If people do not know simply because he does not tell them, then which party is the one who is truly blind?