Hearing loss is a bigger loss than blindness. many would disagree. But it is a fact. When people go into coma, one is asked to keep talking to the patient, it is to keep him alive, grounded to life. The eyes may be closed, mind shut off but hearing is on and the brain is tuned to grab any sounds and specially voices.
To get a better picture of deafness over blindness, one exercise can be done, many would have done, it is from everyday life we all would have experienced in life. Mute the TV and keep looking at the movie or documentary or a song anything. What do you experience? After few minutes, you lose all interest in it after a while and maybe sleep off after a while. Now close your eyes and listen to any CD of your choice, what do you experience? Body starts to react to it, music or speech, your brain is full on into hearing and you are alive. So its the sounds and hearing that keeps us more alert and alive and focused and is very essential to lead life. One needs to develop language for living.