I heard that if a person donate his two eyes it can be kept to minimum of six persons

The reality is that a donated eye is capable of helping more than 1 or 2 people. We would imagine that it is as simple as a person dies and donates their eye. Someone else goes into surgery and within a few hours the doctors manage to pop an old eye out and replace it with the newly donated eye. The reality of it is much different. People suffer from various conditions related to the eye, and each condition effects different parts of the eye for different reasons. That means that a donated eye could easily help bring sight to a blind person, or save the eye of as 6 people easily, and that is probably for just one eye. I don't believe it would be unreasonable at all to help save 8 people between both eyes. It is amazing to consider all of the opportunities we have to be of service to other people, and how many lives we have the ability to impact and change even upon our death.