The U.S. Library of Congress has released a newly-digitized collection of Sigmund Freud's personal writings. 20,000 documents were made available online on Feb. 1.

Quartz reported that the documents included letters with his family as well as his contemporaries such as Carl Jung, Albert Einstein and Thomas Morin. The collection is intended to give the public a better understanding of his theories as well as his personal life.

Archivist Margaret McAleer said that the collection "exposes the complexity of the man and his ideas." It is expected that several scholars will be going over the documents again and again to search for its deeper meanings. McAleer was the one who catalogued the collection.

One letter, written in 1910, was sent to Jung. Freud complained about not feeling well and about the difficulty that he experienced in using allegory in interpretations.

The two scholars had a great friendship early on, with Freud considering Jung as his intellectual heir apparent. However, in 1913, they had a big falling out and ended their correspondence.

The collection has been deemed as the "Sigmund Freud Papers." The letters are mostly in German.

In the Library of Congress' official website, it was noted that the bulk of the material was dated from 1871 to 1939. It is a collection of documents on how Freud founded psychoanalysis as well as how the theory matured and was refined.

Several facets of his life and work are reflected in the collection. This includes his early medical and clinical training as well as his relationship with his family, friends, colleagues, students and patients.

According to The Washington Post, the digitization of the collection took a year and a half. It was funded by the Polonsky Foundation which is a nonprofit organization in the U.K.

Experts on Sigmund Freud agreed with the collection and making it available online. They believe that this would pave the way for more people to be interested in Freud worldwide.