Outlined the behaviorist manifesto in a Psychological Review article, “Psychology as the Behaviorist views it. In 1920, he and Rosalie Raynor reported conditioning a fear reaction in a child called “Little Albert.” The behaviorists emphasized the nurture side of the nature-nurture controversy, and also emphasized the continuity side of the continuity-discontinuity controversy. Moreover, it endorsed determinism over free choice.

Linguist Noam Chomsky publishes a critique of B.F. Skinner’s Verbal Behavior.  Chomsky believed that language was infinitely generative in that with a finite number of words and rules, one could create infinite novel sentences.  Chomsky also proposed the idea that humans had an innate “Language Acquisition Device,” which allows humans to be biologically predisposed to learn language.  He argued that unlike the behaviorist view of language acquisition, humans did not need to be reinforced for speech in order to acquire language.

Thomas Szasz criticizes psyichiatrists and medical doctors and argues that mental illness is simply a euphamism for behaviors disapproved of by society.

Stanley Milgram publishes his classic study of obedience.  Influenced by the events that occurred during WWII, Milgram conducted a study to test the limits of human obedience.  Under the guise of conducting a study of punishment on learning, Milgram ordered participants to administer increasingly powerful electric shocks to a “learner,” (who was actually a confederate and was not receiving any shocks).

When participants protested, they were encouraged to go on, and in the classic studies, over 2/3 of participants, regardless of age, gender, or occupation, went so far as to administer what they believed to be a lethal shock to the “learner.”  Milgram’s study was controversial and served as a catalyst for stricter ethical guidelines in research.

Homosexuality removed from the DSM. The American Psychological Association does not consider homosexuality a mental disorder.

This work, written by biologist Edward O. Wilson, serves as the precursor to the field of evolutionary psychology. Later, in 1976, Richard Dawkins publishes The Selfish Gene, which begins to popularize evolutionary psychology for looking at phenomena such as aggression and sexual behavior.

After John Hinkley Jr. shot President Ronald Reagan in an attempt to impress actress Jodi Foster, he was found not guilty by reason of insanity.  In response to the public outcry, the U.S. congress revised the law in 1984 so that the burden of proof for the insanity defense would rest on the defendant.

Howard Gardener proposes his theory of multiple intelligences.  This theory contrasts the proposal that there is only one type of intelligence, as suggested by IQ tests.  This theory is controversial, and has not been fully researched.  Proposed intelligences include: Linguistic, Logical-Mathematic, Musical, Interpersonal, Intrapersonal, Naturalistic, Spatial, and Bodily-Kinesthetic.

Dr. Jack Kevorkian is indicted for committing physician-assisted suicide.  The issue of “active euthanasia” is controversial in the U.S.

In 2005, the state of Oregon won their case allowing the state to continue the death with dignity act.  This act allows individuals with terminal illnesses (estimated death within six months) to petition the state in order to obtain a prescription for lethal drugs so that they may end their lives.  In 2008, the state of Washington implemented a similar measure.