As I think the hon. Lady knows, the definition to which the National Assistance Board works is contained in Section 64 of the Act, which says: blind person means a person so blind as to be unable to perform any work for which eyesight is essential. Whether a person comes within the terms of that definition is a matter for the ophthalmologist who examines him. If he is partially handicapped, the Board can take that into account in its discretionary allowances.