Was the accused at the time of the commission of the act with which he is charged, and before that time, laboring under such mental disease as to render him certifiably insane? […] He goes on to ask, How is a jury to determine whether a man is " certifiably insane?" How is any man to attach a definite meaning to "certifiably insane?" "The phrase can only mean that a couple of doctors can be found to certify that in their opinion the man is insane."