Joseph Jastrow (1863 - 1944 ) is a psychologist American . He studied at the Johns Hopkins University and became the first American to receive a doctorate in psychology in 1886 . After that he went to the University of Wisconsin and it was there that he introduced the use of hypnosis there around 1889.
Joseph Jastrow is best known for his drawings and his ambiguous optical illusions , illustrating the question "what do you think you see, or do we see what we believe?"
The “duck-rabbit” of Joseph Jastrow, a figure which can be viewed alternatively as a head like a duck or rabbit head.