Yes, the fish could be blind...follow mattrox's directions and watch out for it.
Another thing I was thinking of...you just got the fish? Maybe this one is not used to the tank yet and that's why he is bumping into things. Is he eating -- can he see the food? One of my bettas keeps bumping his "nose" into the side of the tank. He can see, and eat, but he just keeps bumping into the glass. Since it's usually on the one side only (for my fish), maybe it's a reflection that only he can see that's causing him to do this, and maybe your tank has a similar reflection somewhere.