a case of the blind leading the blind

a case of the blind leading the blind

A situation in which an incompetent person tries to guide or teach those who are equally incompetent. That project stalled as soon as it became a case of the blind leading the blind—no one knew what they were doing! Don't ask me to tutor someone in algebra because it would be a case of the case of the blind leading the blind.
See also: blind, case, leading, of