Disabled stereopsis may be the norm among well-educated people

Most well-educated people, where the author lives, have lost the ability to perceive the third dimension in space during everyday life. This has passed unnoticed because poor depth perception is not a serious handicap in an urban environment and because clinical depth perception tests have not been designed to detect this deficit. The author's hypothesis is that disabled stereopsis is a global phenomenon. A simple way of testing for disabled stereopsis is presented, in the hope that investigators in other parts of the world will test a sample of their local population and send the results to the author.