Freud began an interesting venture of analyzing himself. He primarily analyzed his dreams and this self-analysis led to the development of one of his more famous books The Interpretation of Dreams, which was published in 1901. This photo is of Sigmund Freud's office - can you find the three differences in this photo hunt puzzle?
In 1923, Freud wrote one of his most popular books The Ego and the Id. This book brought together new insight on how the process of the mind works.