SMP98 Teaching Talk

Statistics as an Expression of Liberty

John K. Kruschke
Indiana University

Talk presented at
the 31st Annual Meeting of the Society for Mathematical Psychology,
Vanderbilt University, Nashville TN, 8 August 1998.


You can lead a horse to water...

Regardless of the topic, teaching poses two essential challenges:

This talk addresses one way to motivate students to learn statistics.

Motivation is emotional.

The words "motivation" and "emotion" share a similar etymology. A student is motivated to learn when he or she has an emotional investment in the topic. An instructor is motivated to teach when he or she has an emotional investment in the topic.

Good teaching of any topic is motivational and emotional. At the 1998 National Institute on the Teaching of Psychology, Karen Huffman presented a talk about generating "magical moments" in the classroom, by which she meant moments in which instructor and student achieve a sense of fulfillment, i.e., a sense that the classroom experience has made a significant and meaningful impact on the student's life. In essence, she showed that having both teacher and student emotionally and personally invested in the topic leads to fulfilling moments in class.

But how do you, as an instructor, get emotionally invested? She suggested evaluating your own goals, not just as an instructor, but as a human being. Decide what you care deeply about, and bring these values into your teaching.

Now the critical question: How can the topic of inferential statistics be made emotionally engaging? What deeply felt human values can be incorporated into the teaching of statistics?

Provoke the premise.

One method by which to get students emotionally invested in statistics is to pose provocative claims made by celebrities or persons of power, regarding emotionally laden issues such as race, religion, sex, age, drugs, diet/nutrition, and so on. You can probably find current examples in the popular media. I will not pursue examples of these here, as the best ones are the most recent ones and the ones you personally find most compelling.

Presenting provocative claims must be done carefully and considerately, as it involves a risk: Some students might get offended. You, as the instructor, must be careful to present the provocative claims without appearing to espouse them yourself (unless you want to, of course). Do not present any controversial claim that you are not comfortable discussing.

Presenting provocative claims has one major goal:

Ubi dubium ibi libertas.

Crucially, the "you", in "you could be wrong", could be anyone, even a person of power; i.e., a person who controls valuable resources.

People in power sometimes do not like dissent, disapproval, discussion, or disbelief.

Ideas are more powerful than guns.
We would not let our enemies have guns.
Why should we let them have ideas?
-Joseph Stalin.
In every country and every age,
the priest has been hostile to liberty.
-Thomas Jefferson

Only a society with liberty allows open teaching and free use of inferential statistics, because a statistical test is inherently an expression of doubt.

What is the fundamental premise of inferential statistics?

You could be wrong.

What societal and institutional condition is critically necessary for the implications of this premise to be pursued?


Ubi dubium ibi libertas: Where there is doubt, there is freedom.

One device for communicating this to students.

In my graduate statistics class, I communicate these ideas to my students by letting a far more eloquent man, Jacob Bronowski, do it for me. His video series, The Ascent of Man, was broadcast in 1972 and it is still, in my opinion, one of the finest documentary series ever produced. Throughout the series, Bronowski emphasizes that science is human and personal, that science is created by people who are trying to touch reality, and that the products of science in turn touch people.

Episode 11, entitled Knowledge or Certainty, propounds scientific knowledge as a profound expression of human epistemology. Bronowski emphasizes that the entire enterprise of scientific groping for knowledge is, and must be, conducted with inherent tolerance for uncertainty, and with attention to the possibility of error.

Personal notes from my visit to Göttingen.

From The Ascent of Man by Jacob Bronowski
Episode 11: Knowledge or certainty

[The irony of the uncertainty principle amidst the rise of dictators.
The following passage was spoken at the University in Gottingen, Germany:]

Yet the Principle of Uncertainty is a bad name. In science or outside it, we are not uncertain; our knowledge is merely confined within a certain tolerance. We should call it the Principle of Tolerance. And I propose that name in two senses. First, in the engineering sense. Science has progressed step by step, the most successful enterprise in the ascent of man, because it has understood that the exchange of information between man and nature, and man and man, can only take place with a certain tolerance. But second, I also use the word passionately about the real world. All knowledge, all information between human beings can only be exchanged within a play of tolerance. And that is true whether the exchange is in science, or in literature, or in religion, or in politics, or even in any form of thought that aspires to dogma. It is a major tragedy of my lifetime and yours that, here in Gottingen, scientists were refining to the most exquisite precision the Principle of Tolerance, and turning their backs on the fact that all around them tolerance was crashing to the ground beyond repair.

The Principle of Uncertainty or, in my phrase, the Principle of Tolerance, fixed once for all the realization that all knowledge is limited. It is an irony of history that at the very time when this was being worked out there should rise, under Hitler in Germany and other tyrants elsewhere, a counter-conception: a principle of monstrous certainty. When the future looks back on the 1930s it will think of them as a crucial confrontation of culture as I have been expounding it, the ascent of man, against the throwback to the despots' belief that they have absolute certainty.

[Science is a human form of knowledge.
The following passage was spoken at Auschwitz:]

It is said that science will dehumanize people and turn them into numbers. That is false, tragically false. Look for yourself. This is the concentration camp and crematorium at Auschwitz, this is where people were turned into numbers. Into this pond were flushed the ashes of four million people. And that was not done by gas. It was done by arrogance. It was done by dogma. It was done by ignorance. When people believe that they have absolute knowledge, with no test in reality, this is how they behave. This is what men do when they aspire to the knowledge of gods.

Science is a very human form of knowledge. We are always at the brink of the known, we always feel forward for what is to be hoped. Every judgment in science stands on the edge or error, and is personal. Science is a tribute to what we can know although we are fallible. In the end the words were said by Oliver Cromwell: "I beseech you, in the bowels of Christ, think it possible you may be mistaken."

... We have to cure ourselves of the itch for absolute knowledge and power. We have to close the distance between the push-button order and the human act. We have to touch people.

Thus, properly conducting a statistical test is a profoundly human act, and is an expression of liberty.

Conclusion: Profess your passion.

An imperative:

When you teach - even statistics - find ways to make it personal, emotional, passionate; first for yourself, then for your students.

The reward:

When it's emotionally compelling for you, teaching it is compelling.

When it's emotionally compelling for your students, they will value what you and our colleagues do. They will support it personally, philosophically, politically and economically.

Teaching passionately is just enlightened self interest.

Epilogue: The price of liberty and the role of tenure.

"It is the common fate of the indolent to see their rights become a prey to the active. The condition upon which God hath given liberty to man is eternal vigilance; which condition if he break, servitude is at once the consequence of his crime and the punishment of his guilt."
-John Philpot Curran: Speech upon the Right of Election, 1790. (Speeches. Dublin, 1808.)

"Eternal vigilance is the price of liberty."
-abolitionist Wendell Phillips (1811-1844) paraphrasing John Philpot Curran (above)

Students, both undergrad and grad, are shockingly unaware of the purpose of tenure. Stats class is a great venue for explaining tenure.

Students first need to be reminded that the reasonably pursued truth is not always flattering to people in power, and that some people in power will suppress their detractors. Hitler and Stalin and Pol Pot are good dramatic examples of ruthless power wielders. Remind students that United States Supreme Court Justices have tenure so that they can interpret the Constitution as they see it, without threat of losing their position by the capricious decision of someone in power.

Here are some examples of victims in science:

Students should also be told that tenure is only a partial guarantee. Tenure does not guarantee any particular salary level, nor does it guarantee funding for research projects, nor does it guarantee lack of harassment.

Post script: Teach skepticism not cynicism.

The overarching goal is to turn students into passionate and principled critical thinkers. They should be reasonably skeptical in all things.

Skepticism can, and should, also be directed at purveyors of statistical results. A claim bolstered with statistical results must be critically examined, as we all know "How to lie with statistics" (Huff, 1954). But this recursive skepticism must be taught carefully, lest we inadvertently turn students into cynical relativists, the exact opposite of principled critical thinkers.

My hope is that students come away from a course in statistics with a feeling that statistical tests are a profound expression of liberty, and are an exquisitely developed and still developing set of methods for expressing doubt and pursuing the truth.

Copyright © 1998 by John K. Kruschke