In addition to creating the psychoanalytic process, Freud came up with quite a few theories about the minds of humans. Many of these theories were rather shocking for the times in which he lived. Here are several of his more memorable ones.
- Oedipus Complex: Freud's most well-known theory, the Oedipus Complex says that boys develop a sexual attraction toward their mothers at a certain age. This attraction can become so powerful that a boy may become very jealous of his father, and even come to hate him.
- Id, Ego, Superego: In 1923, Freud theorized in "The Ego and the Id" that the mind is divided into three compartments: the id, the ego and the superego. These aren't physical divisions, but rather conceptual ones. The id resides in our unconscious mind and is driven toward physical gratification, such as breathing, eating and sex. The ego works toward satisfying the id's desires in a safe manner, while the superego's goal is moral and socially acceptable behavior. Often, these three parts of the brain compete with one another [sources: McLeod].
- Penis Envy: This theory says females begin wishing for a penis at a young age, and the desire intensifies over time. The reason? Boys have more fun with their Johnsons than girls do with their own sexual organs. Freud further theorized that as girls grow up, their penis envy manifests itself by a deep love for their dads, and the desire to have a son — because these are the closest they'll ever get to having a penis of their own [source: Kubota].
- Freudian Slip: In his 1901 publication "The Psychopathology of Everyday Life," Freud said that when you make a slip of the tongue — e.g., "This is the breast I can do" — it's not an accident at all. Instead, it's your unconscious mind revealing your secret, true thoughts [source: PBS].
- Anal Retentiveness: Our sexuality begins when we're very young, and progresses through several stages. The first is an oral fixation at infancy, followed by an anal fixation at ages 2 to 4. During this anal stage, which coincides with toilet-training, toddlers may develop an anal-retentive fixation if they are punished too often during training. These kids hold onto their feces and become focused on tidiness, order and perfectionism. (To round out Freud's theories on infantile sexuality: At 5, children pass through a phallic stage, when they see their sex organs as a source of pleasure, followed by a latent period when they lose interest in sex and usually the opposite sex. At puberty, they enter a genital phase where their mature sexual development begins. A mentally healthy adult must have successfully passed through each stage.)
- Defense Mechanisms: As part of his theory on the id, ego and superego, Freud said the ego employs one of several defense mechanisms to stave off negative, unpleasant feelings from our conscious minds [source: McLeod].
- Denial. Blocking something from your awareness. Example: Refusing to believe the doctor's report that you have cancer.
- Displacement. Using a substitute object to satisfy an impulse. You punch a wall when you're angry at your friend.
- Projection. Ascribing your thoughts to another. For instance, you dislike someone, so you believe they hate you.
- Regression. Moving back in time when you're stressed. You suck your thumb when faced with a tight deadline.
- Repression. Unconsciously blocking disturbing thoughts. Example: Your mind won't let you remember when you were sexually assaulted.
- Sublimation. Satisfying an impulse in a socially acceptable way. You go out for a run when you're angry at your friend.
So how do these theories hold up today? We'll find out on the next page.