SIGMUND FREUD: BIOGRAPHY, THEORIES, CONTRIBUTIONS, WORKS - PSYCHOLOGY - 2024

Sigmund Freud (1856 - 1939) was a neurologist who became famous as the father of psychoanalysis. His intellectual and philosophical contributions gave a new vision to the western thought of the 20th century.

He revolutionized the approach to psychiatry and psychology, by creating concepts and theories that broke with established methods. Psychoanalysis not only changed the way of interpreting and treating mental illness, but it also shaped aspects of the culture of the time.

Sigmund Freud, by Max Halberstadt (1882 - 1940), via Wikimedia Commons. Freud managed to show a new key aspect in the construction of the concept of humanity, with which he left aside the social, religious and economic man, and showed in the foreground the psychological man, whose behavior goes not only hand in hand with external elements.

Sigmund Freud's postulates shed light on the structure and functioning of the psyche. Among other points, he stated that the root of behavior lies in repressed desires or thoughts.

Despite this, many of the dogmas that govern psychoanalysis cannot be verified and are accused of having little scientific rigor, which is why it is considered by some a philosophical school rather than a scientific one.

Important data

The concepts that Sigmund Freud popularized sooner rather than later became fundamental pieces of the culture of the 20th century, as well as of the popular imaginary of society to this day.

He influenced various fields, one of the most prominent being surrealism in painting, whose great exponents took the interpretation of dream scenes as a starting point for their creations.

The methods proposed by Sigmund Freud were evolving. At first he defended the use of hypnosis and the cathartic method, in which the patient recalled repressed memories. Then he discovered that free association and dream interpretation could work better.

Biography

Sigismund Schlomo Freud was born on May 6, 1856 in Freiberg, a Moravian town in the then Austrian Empire. The city in which the future father of psychoanalysis took his first breaths is currently called Příbor and is in the Czech Republic.

His father was Jakob Freud, a middle-aged man (41 years old at the time of Sigmund's birth), who was involved in the wool trade and came from a family of Hasidic Jews, although he himself was considered a freethinker.

Freud's mother was a young woman named Amalia Nathansohn, who was Jakob's third wife. Sigmund had two older brothers from his father's first marriage, plus a nephew who was a year older and with whom he had a very close relationship.

He had seven younger siblings, five girls and a boy managed to survive, while another died during childhood.

At the time, the financial situation of the Freuds was difficult in their hometown. So Jakob felt that the best option was to take his family to a more developed city. In 1859 they moved to Leipzig where they stayed for a year.

In 1860 they decided to settle in Vienna, where he spent most of Sigmund Freud's life.

Education

Despite the fact that the Freud family did not have a good economic position, Jakob made the necessary efforts to provide a high-quality education for the eldest of the children of his third marriage, Sigmund.

In 1865 Freud entered the Leopoldstädter - Kommunal - Realgymnasium. There he stood out among his peers and did not waste the opportunity that his parents insisted on giving him. On the contrary, he knew how to dignify them when he received honors in 1873.

Sigmund Freud had a good disposition for learning languages ​​early on. Among the languages ​​he mastered were German, French, Italian, English, Spanish, Hebrew, Latin, and Greek.

It was debated for a time between the two professions that were then offered to young Jews: law and medicine.

An account of the time asserts that he chose the option of becoming a doctor after listening to a text written by Goethe about nature. Although it was the profession he selected, he was not a great admirer of the profession of doctor and even classified it as "repulsive".

What did attract his attention powerfully was becoming a scientist. His main ambition from the beginning was to broaden knowledge about the human condition.

Medicine

After beginning his career at the University of Vienna, Freud received classes from professors such as Franz Bertrand, who taught philosophy. He also took lessons with Carl Claus who was the professor of zoology.

However, his greatest mentor during these years was Ernst Brüke, director of the Laboratory of Physiology at the University of Vienna, where Sigmund Freud spent six years doing research in the area of ​​neurology.

His main branch of interest at the beginning of his career was the human brain, specifically the composition of its tissues, and the research he carried out contributed to the later discovery of neurons.

After becoming a specialist in neurology, Freud received the degree of doctor of medicine in 1881, when he was 25 years old.

While working in Brüke's laboratory, Freud met one of his great friends, Joseph Breuer, from whom he learned a lot and who served as a role model early in his career.

In 1882 Sigmund Freud began working as a clinical assistant to Theodor Meynert, a psychiatrist at the Vienna General Hospital. He also spent time serving under Hermann Nothangel, an internist at the same health center.

First love

Another important event in Freud's life during 1882 was meeting Martha Bernays, to whom he became engaged. The young woman came from a very influential and wealthy family, which is why, at that time, a recently graduated boy did not meet the expectations of Martha's father.

Although they did not oppose the future union of Freud and Bernays, they concluded that it was preferable to wait a while, so that the boy would have time to get a name and with enough status to be able to provide what is necessary for Martha and the family that they were to form.

Cocaine Research

In 1884 Sigmund Freud published a study on the therapeutic properties of cocaine (Über coca). Although practical applications were later discovered in which cocaine could be used as a painkiller, Carl Koller took all the credit for that, as he did not cite Freud.

Overall, this research proved a failure for Freud who wanted to find antidepressant properties in the substance.

Not only did he not achieve the expected results, but his image was called into question, especially because he failed in trying to cure Ern von Fleischl-Marxow's addiction to morphine.

Instead of saving his friend from his primary addiction, he made him dependent on cocaine, and eventually von Fleischl-Marxow passed away. Freud himself came to experiment with this substance, although he never developed an addiction.

Paris

Despite the setback caused by the cocaine incident, Freud was appointed professor of neuropathology at the University of Vienna in 1885, but the position did not generate any financial benefits.

That same year he won a scholarship that allowed him to travel to Paris, France, for 4 and a half months. There, Sigmund Freud was able to spend time at the Salpêtrière Clinic and worked with one of the figures that caused him great admiration: Jean-Martin Charcot.

He knew first-hand the French method for treating patients who presented “hysteria” and it was this who introduced him to an important question that was the basis for his entire life as a professional: Could the root of the problems lie in the mind and not? in brain?

Charcot used a treatment that consisted of inducing hypnosis to the patient and then applying suggestion to alleviate his condition. For a time the subject could show improvement in hysteria symptoms.

Private career

In early 1886 Sigmund Freud returned to Vienna and established his private practice. During those years he used to exchange many ideas with Joseph Breuer, who referred him the case of one of his patients: Anna O.

At this time, Sigmund was fortunate to be Breuer's apprentice, and he marveled at the method his mentor used with Anna O. The impact of this story on psychoanalysis was profound.

Among other symptoms, the woman had developed partial paralysis, could not drink water and had forgotten her mother tongue (German), so she communicated in French. During hypnosis, memories that she had not awake appeared and after talking about them, her symptoms disappeared.

This method Breuer called the "speech cure" and was used by Freud in his early years as a therapist.

However, with the passage of time Freud could notice that by laying the patient on a comfortable sofa (divan), placing himself in a place far from the person's sight and requesting that he express everything that was going through his mind, those memories also appeared.

Sigmund Freud called this method "free association."

Marriage

Sigmund Freud and his family

In September 1886 the union so longed for by lovers took place: Sigmund Freud and Martha Bernays married. He had managed in four years to procure an adequate status for the girl's parents to agree to his wedding.

They moved to the historic district of Vienna, to an apartment in which they would spend most of their lives. Despite the fact that Freud was extremely jealous of his wife and resented all the affections she possessed, including that of his mother-in-law, the couple had a lasting marriage.

Some claimed that Martha was one of the great supports in Freud's life and that her support was key to the development of his scientific career. In 1887 the Freud's first daughter was born, whom they named Mathilde. Two years later a man named Jean-Martin arrived.

Oliver was born in 1891 and he was followed by Ernst a year later. Sophie, the second daughter came to the family in 1893 and Anna the youngest, and successor to her father's work in the world of psychoanalysis, was born in 1895.

Freud and his daughter Anna

In 1896 Minna, Martha's sister, moved into the Freud house and her closeness to Sigmund sparked all sorts of rumors claiming they were lovers.

Beginnings of psychoanalysis

In 1895 Sigmund Freud and Joseph Breuer published a joint work which they called Studies on Hysteria. There the idea of ​​psychoanalysis was sown, although it had not yet been fully developed.

The following year both the relationship of intellectual collaboration and the friendship between Breuer and Freud ended, because the first did not consent to Freud's approach in which he seemed to indicate that all problems have a sexual root.

The father of psychoanalyst also had a close friendship with Wilhelm Fliess, with whom he discussed his ideas about the new model for approaching the human mind and its problems.

Bisexuality and child sexualization are some of the points that are believed to have been influenced by Fliess's vision.

Freud and Fliess

In 1896 the term "psychoanalysis" had been formally coined and used by Freud. He concluded among other things that the memories of early sexual events expressed by the patients were not real, but repressed desires that could degenerate into mental pathology.

This, together with the self-analysis to which he underwent since 1886, in which he discovered his secret hostility towards his father and the competition for the mother's affection, led him to generate one of the basic theories of psychoanalysis: the Oedipus complex.

Theoretical development

In his second work The Interpretation of Dreams, Sigmund Freud began to refer to the mental structure in its three stages: the unconscious, the preconscious and the conscious.

In addition, he coined another important term such as "libido", with which he referred to a mental energy, although he did not specify that it was only related to the sexual impulses of the individual.

The public became very interested in his work, especially after he raised the analysis of dreams as one of the Freudian methods. Freud considered the dreamlike to be a direct route to the unconscious.

The impact of this was not only framed in psychoanalysis but also reached popular culture.

Freud continued to build the theoretical foundations of psychoanalysis in later works such as:

- The psychopathology of daily life, 1902.

- Jokes and their relationship with the unconscious, 1905.

- Three essays on the theory of sexuality, 1905. In this he coined terms such as "drives" and "polymorphic perverse", he also argued that there were the bases of the sexual identity of individuals.

First followers

Around 1902 Sigmund Freud began to be recognized, as did his novel theory; psychoanalysis. He received a position at the University of Vienna, being appointed as an extraordinary professor.

Although that position was devoid of salary or fixed classes within the college, it gave him great prestige as a doctor.

Some think that Baroness Marie Festrel may have played a role in Freud's appointment.

Also during this year other doctors interested in Freudian theories decided to start meeting. The day they scheduled their meetings, he named his group: Wednesday Psychological Society.

They especially discussed cases of psychology and neuropathologies. There psychoanalysis ceased to be an isolated theory or practice, used only by its creator, and became a current, it was not an isolated method.

The original members of the society, all of Jewish origin, were: Sigmund Freud, Wilhelm Stekel, Alfred Adler, Max Kahane and Rudolf Reitler.

But the movement did not stop and by 1906 the society had 16 members. That same year Freud began to share ideas with Carl Jung, who was already known in the academic and research circles; in 1907 Jung joined the Wednesday Psychological Society.

Expansion

In 1908, he decided to create a new institution that was more appropriate for the impact that psychoanalysis was generating on the intelligentsia of the time. The new name used was the Psychoanalytic Society and Freud was named its president.

Chapters were formed in other cities such as Zürich. That same year the first formal meeting of all affiliates was held at the Hotel Bristol in Salzburg. 42 people attended and it was decided to create a publication (Jahrbuch für psychoanalytische und psychopathologishe Forschungen) which was left to Jung.

International boom

In 1909 Sigmund Freud, Carl Jung and Sándor Ferenczi were invited to give lectures on psychoanalysis at Clark University, Massachusetts, United States. There, too, the father of the movement received an honorary doctorate that raised his reputation to the sky.

They aroused the interest of both the media and such figures as James Jackson Putnam, who, along with Ernest Jones, founded the American Psychoanalytic Association in 1911. At the same time, Abraham Brill created the New York Psychoanalytic Society.

Alfred Adler and Wilhelm Stekel started a monthly magazine in 1910. The following year Otto Rank started another publication in which he approached culture and literature from a psychoanalytic perspective.

In 1910 Adler began to chair the Psychoanalytic Society. That same year the first woman named Margarete Hilferding joined and in 1911 two new female members joined, Tatiana Rosenthal and Sabina Spielrein, both Russian.

During the 1910 Nuremberg Congress the International Association of Psychoanalysts was founded and Carl Jung was chosen as president with the approval of Sigmund Freud.

Breaking off

The first member to begin to dissociate himself from Freudian ideas was Alfred Adler. Freud had left him in charge of the Psychoanalytic Society for the purpose of containing his theoretical differences and providing him with a degree of authority in the circle.

Since 1909 both had different ideas about neuroses, but it was not until 1911, during the meeting in Vienna, that Adler resigned his position as president of the Psychoanalytic Society and separated from the group, seconded by Stekel, who served as vice president..

Stekel, along with Adler and nine other members, formed the Society for Free Psychoanalysis, which they later renamed the Society for Individual Psychology.

Carl Jung's psychology of the unconscious came out in 1912 and through it, the author broke with the points proposed by Sigmund Freud. The name of Jung's new theory was "Analytical Psychology" and with it he supplanted psychoanalysis.

At that time, Jones, anticipating the new break, started what he called the "Committee of the Loyalists" (1912) whose function would be to protect the ideas and theoretical coherence of psychoanalysis. The members were Freud, Jones, Abraham, Rank, Ferenczi, and Sachs.

However, Jung continued attached to the current until 1914, when he resigned as president of the International Association of Psychoanalysts and definitively started from the Freudian postulates.

Introduction to psychoanalysis

Sigmund Freud continued to add to the theories of psychoanalysis with works such as On Narcissism, in which he mentioned for the first time a fundamental concept the "ideal self" that was transformed over time into the "superego."

Between 1915 and 1917 Freud dictated and later published a series of lectures at the University of Vienna, which he called Introduction to Psychoanalysis.

The expansion of the movement did not end, Ernest Jones founded the London Psychoanalytic Society (1913), which in 1919 became the British Psychoanalytic Society, without the Jungian members. The last was chaired by Jones until 1944.

Jones was also the founder of the Institute of Psychoanalysis in 1924 and of the London Psychoanalysis Clinic, both of which were directed by him.

Beyond the pleasure principle (1920) was the witness to Freud's deepening of a controversial topic such as "drives". Then The I and the Id represented a watershed in Freudian theory.

Cancer

In 1923 Freud was diagnosed with cancer of the palate, although some claim that the diagnosis was hidden from him for fear that he would decide to end his life. The father of psychoanalysis had been a cigar smoker for most of his life.

This disease led to Freud having to undergo surgery more than 30 times. His health and physical abilities also declined, he became deaf in his right ear and had to wear a palatal prosthesis for a time.

He never gave up the habit of tobacco, even when, according to some historians, it was recommended to him by some of his doctors. However, it is remarkable that it was not until the 1950s that the effects of tobacco became widely known.

In the same year as the publication of The Discomfort in Culture (1930), Freud received the Goethe Prize for his contributions to German psychology and literature.

When Hitler and the German National Socialist Party came to power in 1933, the famous book burning took place.

Among titles were works by Freud and other psychoanalysts. However, this did not cause alarm in its founder who was confident that this event would not pass to greater.

Flight from Vienna

In 1936 Sigmund Freud was appointed a member of the Royal London Society for the Advancement of Natural Science. By this time, the father of psychoanalysis still did not think that he would have to leave the country.

It was in 1938, when the Germans occupied Austria, that the real persecution for him and his family began. Being a Jew and a psychoanalyst, he was classified as an enemy of the Third Reich.

Although he did not want to leave Austria, two events led him to realize that his departure was imperative. They raided his home and a publishing house of psychoanalytic material, throughout the day they kept his son Martín in custody.

Then the Gestapo questioned his youngest daughter and the one closest to him: Anna Freud. She was transferred to headquarters and there they proceeded to submit her to a series of questions.

One of his most influential patients was Marie Bonaparte, a descendant of Napoleon. Thanks to her, Ernest Jones, Freud and some of his relatives were able to secure conduits to leave the country.

Sir Samuel Hoare and another of his former patients, the United States Ambassador to France William Bullitt, also assisted in the process. Before leaving, the Nazis made them sign a document stating that they had been "treated with respect."

Years in London

Before going to England, the Freuds passed through France and stayed for a few days at Marie Bonaparte's residence. There, personalities such as Salvador Dalí, father of surrealism, and Leonard and Virginia Woolf came to meet her and express their respect for her.

Four of Freud's sisters failed to get their safe-conducts processed and all died later in a Nazi concentration camp.

The Freuds were finally able to settle in London. Sigmund's Vienna office was recreated almost perfectly in his new home.

He received patients until his health allowed it and in 1938 he published Moses and Monotheism, then he was already very affected by cancer.

Death

Sigmund Freud passed away on September 23, 1939 in London, England. He had been suffering from intense pain caused by his illness for a long time, his suffering being such that he could no longer perform almost any daily activities.

He went to his friend and Dr. Max Schur, and reminded him of a promise that he had made: not to let him suffer agony for no purpose. Freud told him that his life was a constant torture and that if his daughter Anna agreed he wanted to end the suffering.

Although at first the youngest Freud did not want her father to die, she finally agreed and on September 21 and 22 she was given morphine injections, which in the early morning of the 23 led to the death of the Austrian doctor.

There has been speculation as to whether Freud was given a third injection and it has been said that Josephine Stross was responsible for doing it, although it was not confirmed.

On September 26, his remains were cremated at the Golders Green Crematorium and deposited in a Greek crater given to him by Marie Bonaparte. When his wife Martha passed away in 1951 her remains were joined with those of Sigmund Freud.

Theories

Unconscious

One of the key points for Freudian theories was the psychic structure in which a clear difference was made between the three states that Freud considered to exist in the human mind: the unconscious, the preconscious and the conscious.

The Austrian doctor argued that in philosophy and other areas these mental states, especially the unconscious, were accepted while psychology had relegated them to the background.

For Freud the individual tends to repress some ideas. However, it does not discard them completely, but they continue within the mind although not in the conscious stage. These ideas or desires can reappear under specific circumstances in the state of consciousness.

In this theory, unconsciousness is not a higher state of mind, that is, a superconscious, but is a separate chamber of consciousness to which it will never have access.

However, some details of what inhabits the unconscious in dreams, jokes, lapses and other episodes can be revealed, giving rise to the so-called preconscious.

Since the only thing that can be known about what inhabits the unconscious is what permeates the preconscious, psychoanalysis represents a model of translation of the message that the unconscious sends to the individual.

Dreams

Although the dream usually hides messages from the unconscious, in a normal state, its meaning is usually disguised so as not to disturb the individual, so it is not easy to decode it.

The richest content in information is that which arrives in conflict states in which unconsciousness tries to manifest itself and is blocked by the "I".

According to Freud, the content of dreams is usually monitored and censored by the preconscious in order not to wake up the sleeping person.

At the time of analyzing them, Freud recommended the use of free association, but he also instructed a large number of rules and limitations, among which are:

Do not use it as an isolated method but as part of the psychoanalytic process, nor include superstitions or personal projections of the therapist in the interpretation, nor work on the dream analysis in the absence of the patient.

Psychosexual development

For Sigmund Freud, each individual experiences different phases on their way to sexual maturity. It begins in childhood when, according to psychoanalytic theories, children are "polymorphic perverse" since they have an instinctive libido.

At that first moment, children still do not have the capacity for moral evaluation or shame, so they could carry out any practice that generates satisfaction. From their birth they will experience different phases, which according to Freud are:

- Oral: Between 0 and 1 year.

- Anal: Between 1 and 3 years.

- Phallic: Between 3 and 6 years.

- Latency: Between 6 years and puberty.

- Genital: From puberty to death.

It was in this context that Freud developed his theory about the Oedipus complex, in which the infant has an unconscious sexual desire for his mother and feels, at the same time, hatred and envy for his father.

According to this theory, it is at this stage that the "castration complex" occurs in males and "penis envy" in females. In the case of women, then their unconscious sexual desire directed at the mother changes, taking the father as an object and their hatred is directed at their mother.

Ello, me and superego

For Freud, the psychic apparatus had three major sections that constituted the mental structure. The id controls the instincts of the human being, on the other hand, the superego is in charge of enforcing moral guidelines.

In this case, the self is the mediator between both extremes and it reconciles a balance adapted to reality.

The structure proposed by Freud is solely psychic, since it does not correspond to any specific place in the brain or an area dedicated to carrying out these processes.

This model has its analogy with the first structure proposed by Sigmund Freud, the id and the subconscious have a similar task and process, they cannot be known without the mediation of the ego in one case and the preconscious in the other.

Drives

They are the forces derived from somatic tensions that, even, can go against the instincts. Freud showed the differences between the concepts of instinct and drive.

He described the first as an impulse caused by body tension and excitement that is satisfied by obtaining the object of desire. Meanwhile, he said that drives are never completely satisfied, and they do not have a specific object that can satisfy them.

The drives are not only sexual, that is, those related to libido, but can also be life or death. The former guide the individual toward self-preservation and reproduction, while the latter toward self-destruction.

Contributions to psychology and science

One of the great contributions of Sigmund Freud to psychology and science in general was the fact of approaching the problems of the mind, which always existed with a novel perspective.

He did not focus only on the physical, since he realized that it was mental illness. For a part of the psychology community, Freud was one of the pioneers in the study of the structure of the mind and its functioning.

He undoubtedly broke schemes when it came to human sexuality, although some consider that his approach was wrong.

To a large extent influenced by Charcot and his method of treating women who suffered from hysteria, he managed to discover a simpler model, but better supported, and applicable to both men and women who could present certain mental pathologies.

Also, although many of his theories do not have firm quantitative bases, he brought to the public arena certain diseases that had not been studied until that moment, but which were later approached from a positivist approach, with which other solutions were given.

Criticisms of their work

Criticisms of Sigmund Freud's proposals arose from the beginning of the approach to the theory of psychoanalysis. One of the most relevant attacks that has been made is that the model was not based on the quantitative method and experimentation, which are the foundations of science.

Much more akin to phenomenology than to scientific positivism: psychoanalysis does not meet the basic requirements to trust its theories, methods or processes.

This is what has caused psychoanalysis to be considered by many a "pseudoscience". Also add that your case studies may have been altered. Likewise, its great dependence on metaphors is criticized, which makes it somewhat unreliable.

Another point that has generated great controversy is whether psychoanalysis actually hid a society of pedophiles of the twentieth century, due to proposals such as child sexualization and the naming of children as "polymorphic perverse".

For some psychologists such as Alice Miller and Jeffrey Masson, psychoanalysis goes as far as accusing the infant of sexual abuse committed by adults against him.

The psychoanalytic approach to female sexuality has also been criticized, in which it is shown as a twisted process that is the product of a primary dissatisfaction whose origin occurs in childhood with penis envy.

Complete works

- Vol. I - Pre-psychoanalytic publications and unpublished manuscripts in Freud's lifetime, 1886-1899.

- Vol. II - Studies on hysteria, 1893-1895.

- Vol. III - First psychoanalytic publications, 1893-1899.

- Vol. IV - The interpretation of dreams (I), 1900.

- Vol. V - The interpretation of dreams (II) and On the dream, 1900-1901.

- Vol. VI - Psychopathology of everyday life, 1901.

- Vol. VII - Three essays on sexual theory, and other works (1901-1905), “Fragment of analysis of a case of hysteria” (“Dora” case).

- Vol. VIII - The joke and its relationship with the unconscious, 1905.

- Vol. IX - Delirium and dreams in W. Jensen's «Gradiva», and other works, 1906-1908.

- Vol. X - “Analysis of the phobia of a five-year-old boy” and “On the subject of a case of obsessive neurosis”, 1909.

- Vol. XI - Five lectures on Psychoanalysis, A childhood memory of Leonardo da Vinci, and other works, 1910.

- Vol. XII - Works on psychoanalytic technique, and other works (1911-1913), "On a case of paranoia described autobiographically" (Schreber case).

- Vol. XIII - Totem and taboo, and other works, 1913-1914.

- Vol. XIV - Works on metapsychology, and other works (1914-1916), "Contribution to the history of the psychoanalytic movement."

- Vol. XV - Introductory lectures on psychoanalysis (Parts I and II), 1915-1916.

- Vol. XVI - Introductory lectures on psychoanalysis (Part III), 1916-1917.

- Vol. XVII - “From the history of a childhood neurosis” (Case of the “Wolf Man”) and other works, 1917-1919.

- Vol. XVIII - Beyond the pleasure principle, Psychology of the masses and analysis of the self, and other works, 1920-1922.

- Vol. XIX - The self and the id, and other works, 1923-1925.

- Vol. XX - Autobiographical presentation, Inhibition, symptom and anguish, Can laymen exercise analysis ?, and other works, 1925-1926.

- Vol. XXI - The future of an illusion, The malaise in culture, and other works, 1927-1931.

- Vol. XXII - New introductory lectures on psychoanalysis, and other works, 1932-1936.

- Vol. XXIII - Moses and the monotheistic religion, Outline of psychoanalysis, and other works, 1937-1939.

- Vol. XXIV - Indices and bibliographies.

References

1. Jay, M. (2019). Sigmund Freud - Biography, Theories, Psychoanalysis, Books, & Facts. Encyclopedia Britannica. Available at: britannica.com.
2. Uslar Braun, A. (2005). Up to 100 men. Caracas: The Books of El Nacional, pp.61-63.
3. En.wikipedia.org. (2019). Sigmund Freud. Available at: en.wikipedia.org.
4. Thornton, S. (2019). Freud, Sigmund - Internet Encyclopedia of Philosophy. Iep.utm.edu. Available at: iep.utm.edu.
5. Wollheim, R. (1972). Sigmund Freud. München: Deutscher Taschenbuch-Verlag.