"That so few now dare to be eccentric marks the chief danger of the time."

John Stuart Mill was born May 20, 1806 in London.  His father was James Mill, an historian, philosopher, and social theorist.  His mother was Harriet Barrow, and seems to have had next to no influence on him!  His father decided to use the principles of utilitarianism and associationism (in consultation with his good friend, Jeremy Bentham) to educate John "scientifically."

This seemed to work quite well:  John began learning Greek at three, Latin at eight.  At 14, he studied French, mathematics, and chemistry in France.  At 16, he began working as a clerk for his father at India House, headquarters of the East India Company.  By 18, John was publishing articles on utilitarian philosophy!

But at 20, he had a nervous breakdown, which he describes in his Autobiography (1873).  He attributed it, no doubt rightly, to his rigid education.

In 1830, he met Harriet Taylor, a married woman.  He remained loyal to her until her husband died 21 years later (!), at which point they married.  Sadly, she died only seven years later.

During this time, he served as an examiner for the East India Company.  He also served as a liberal member of Parliament from 1865 to 1868. ("Conservatives are not necessarily stupid, but most stupid people are conservatives.")  He died at his home in Avignon, France, on May 8, 1873.

His best known work is On Liberty, published in 1859.  His most important work as far as science and psychology are concerned is A System of Logic, first printed in 1843 and going through many more editions through the rest of the 1800's.

He began with the basics established by Hume, his father James Mill, and others:

1. A sensory impression leaves a mental representation (idea or image);
2. If two stimuli are presented together repeated, they create an association in the mind;
3. The intensity of such a pairing can serve the same function as repetition.

But he adds that associations can be more than the simple sum of their parts.  They can have attributes or qualities different from the parts in the same way that water has different qualities than the hydrogen and oxygen that compose it.  So J. S. Mill's associationism is more like "mental chemistry" than mental addition.

1. S. Mill agrees with Hume that all we can know about our world and ourselves is what we experience, but notes that generalization allows us to talk with some confidence about things beyond experience.  And he believed that there are real causes for consistent phenomena!

This is often called phenomenalism.  He defines matter, for example, as "the permanent possibility of sensation."  This persepctive would have profound effects on 20th century logical positivism (Wittgenstein, Ayer, Schlick, Carnap, and others) who provided the philosophical foundation for most behaviorists.

He promotes a scientific method that focuses on induction:  Generalizations from experiences lead to theory, from which  we then develop alternative hypotheses;  We go on to test these hypotheses by observation and experiment, the results of which allow us to improve theory, and so on.  This circular notion of scientific progress is known as the hypothetico-deductive method.  In this way we slowly build up laws of nature in which we can be increasingly confident.  This method proved to be very popular among the scientists of his day.

He more specifically outlines five procedures for establishing causation.  The simpler ones go like this:

1. The method of agreement:  If a phenomenon occurs in two different situations, and those two situations have only one thing in common, that "thing" is the cause (or effect) of the phenomenon.
2. The method of differences:  If a phenomenon occurs in one situation but not in another, and those two situations have everything in common except for one thing, then that "thing" is the cause (or effect) of the phenomenon.
3. The method of concomitant variations:  If one phenomenon varies consistently with the variations of another phenomenon, one is the cause or effect, or is otherwise involved in the causation, of the other.  This, of course, is the foundation for correlation which, although it cannot establish the direction of causality, does indicate some causal relationship.

When it comes to psychology, he argued that it could indeed someday become a science, but was unlikely to ever be an exact science.  Predicting the behavior of human beings may be forever beyond our abilities, leaving us to limit ourselves to talking about tendencies.

His utilitarianism recognizes that happiness is not restricted to physical pleasures (or the avoidance of pain), that there may be different kinds or qualities of happiness.  "It is better to be a human being dissatisfied than a pig satisfied; better to be Socrates dissatisfied than a fool satisfied."  So, although we certainly begin as simple pleasure-seeking creatures, over time we can acquire far more humanistic motivations.  Ultimately, this means that high moral values can be taught, and are not dependent on innate qualities of character.

When looking at social issues, J. S. Mill applies his expanded utilitarianism:  Does a certain institution add to human welfare?  Or are there better alternatives?  He argues, for example, that women should be allowed to vote because women's self-interests can add balance to men's self-interests, and lead to a better society.  He argues for personal freedom because it allows creative individuals to better contribute to society.  On the other hand, he notes that free-market capitalism tends to result in inequity and poverty, and we would be better served by some form of socialism.