Sigmund Freud (1856 to 1939) was an Austrian neurologist born in Freiberg, in the Moravian region of the Austrian Empire, now Příbor in the Czech Republic. He trained in Vienna and built his early reputation on the study of nervous disorders, and he went on to develop psychoanalysis, a method and theory centred on the unconscious mind.

He is best known for The Interpretation of Dreams, published in 1899 with a title page dated 1900, and for his later model of the psyche as id, ego and superego. Much of his work grew out of conversations with patients, including the early case of Anna O., which he discussed with Josef Breuer. He was driven by curiosity about why people repeat painful patterns and how memories, wishes and conflicts shape behaviour.

The person who ends up texting this version is often a student, a reader curious about how psychology began, or someone who wants to test Freud's ideas against later research. Those conversations usually compare his claims with modern evidence, where many of his ideas have not held up, and that comparison is part of the point.