I am looking for the title to a 1960's short story about a man who discovers that he is an android after an accident. He discovers how to open the control panel in his stomach area and finds his programming or his "life" is on a very slowly moving punch tape that is read by an optical scanner. He punches extra holes into the tape and finds that it alters his reality. In the end...
he decides to terminate himself since he isn't human and none of what he perceives is real, it's only programming. He slices the tape just before it goes under the scanner knowing this will end his program and his "life".