As I am seldom in a position to deal with active medical matters, I can only report one mistake from my own experience. I treated a very old woman, whom I visited twice daily for several years. My medical activities were limited to two acts, which I performed during my morning visits: I dropped a few drops of an eye lotion into her eyes and gave her a hypodermic injection of morphine. I prepared regularly two bottles--a blue one, containing the eye lotion, and a white one, containing the morphine solution. While performing these duties my thoughts were mostly occupied with something else, for they had been repeated so often that the attention acted as if free. One morning I noticed that the automaton worked wrong; I had put the dropper into the white instead of into the blue bottle, and had dropped into the eyes the morphine instead of the lotion. I was greatly frightened, but then calmed myself through the reflection that a few drops of a _two per cent_. solution of morphine would not likely do any harm even if left in the conjunctival sac. The cause of the fright manifestly belonged elsewhere. In attempting to analyse the slight mistake I first thought of the phrase, “to seize the old woman by mistake,” which pointed out the short way to the solution. I had been impressed by a dream which a young man had told me the previous evening, the contents of which could be explained only on the basis of sexual intercourse with his own mother.[48] The strangeness of the fact that the Œdipus legend takes no offence at the age of Queen Jocasta seemed to me to agree with the assumption that in being in love with one’s mother we never deal with the present personality, but with her youthful memory picture carried over from our childhood. Such incongruities always show themselves where one fantasy fluctuating between two periods is made conscious, and is then bound to one definite period. Deep in thoughts of this kind, I came to my patient of over ninety; I must have been well on the way to grasp the universal character of the Œdipus fable as the correlation of the fate which the oracle pronounces, for I made a blunder in reference to or on the old woman. Here, again, the mistake was harmless; of the two possible errors, taking the morphine solution for the eye, or the eye lotion for the injection, I chose the one by far the least harmful. The question still remains open whether in mistakes in handling things which may cause serious harm we can assume an unconscious intention as in the cases here discussed.