This is a kind of light burn of the retina, when a person stays for a long time in the polar or high-mountain areas in an abundance of snow and sun. Snow reflects the sun’s rays, which hit the retina and damage receptor cells. This can lead to partial or complete loss of vision, which has been experienced by many polar explorers or mountain climbers. In such situations, the eyes must be protected with special glasses.
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.