Dear President Trump:

Fifty-five years ago this week President John F. Kennedy hosted a dinner honoring Nobel Prize laureate scientists, remarking:

I think this is the most extraordinary collection of talent, of human knowledge, that has ever been gathered together at the White House, with the possible exception of when Thomas Jefferson dined alone.

In fact, Kennedy added, the author of the Declaration of Independence and 3rd President of the United States “could calculate an eclipse, survey an estate, tie an artery, plan an edifice, try a cause, break a horse, and dance the minuet.”

From the earliest days of our nation, science has been at the forefront of what makes America great. Thomas Jefferson, Thomas Paine, Benjamin Franklin, James Madison, John Adams and many of the other founding fathers were either practicing scientists or were trained in the sciences. They deliberately adapted the scientific method of gathering data, running experiments, and testing hypotheses to their construction of our nation. Their understanding of the provisional nature of findings led them to develop a political system in which doubt and disputation were the centerpieces of a functional polity.

They thought of political governance as a problem solving technology rather than as a power grabbing opportunity. They thought of democracy in the same way that they thought of science—as a method, not an ideology. They argued, in essence, that no one knows how to govern a nation so we have to set up a system that allows for experimentation. Try this. Try that. Check the results. Rinse and Repeat. That is the heart of science.

For example, there are 50 different states, each with its own constitution and set of laws. These are 50 different experiments. For example, every state has different gun control laws, so we can treat these as experiments from which we can gather results and draw conclusions: states with more guns and fewer controls have higher homicide and suicide rates.

Every time an amendment to the Constitution is ratified and enacted into law, that is an experiment. The 19th Amendment that granted women the right to vote in 1920 worked, so we still abide by it. By contrast, the 18th Amendment passed in 1919 that prohibited alcohol to test the hypothesis that it would reduce drinking and crime failed, so in 1933 the 21st Amendment was enacted, overturning it. Changing your mind when the evidence changes is a virtue, not a vice.

The centuries long experiment of using torture and the death penalty to deter crime also failed, so most states abandoned the practice in favor of other methods that work.

These are not controlled laboratory experiments like physicists and biologists run, but they are real-world experiments whose results are nevertheless valuable to social scientists, policy makers, and the public.

For example, policy experiments showed that teaching abstinence in sex education classes does not stop teens from having sex, and criminalizing abortions did not curb the practice. In both cases, information and contraception works better.

Foreign policy decisions are also experiments. For example, the United States intervention in Germany in 1941 was an experiment that very likely prevented the deaths of millions of people. The United States not intervening in Rwanda in 1994 was an experiment that very likely resulted in many more deaths. The United States intervention in Iraq appears to have been a failed experiment, whereas the result of today’s experiment of intervening in Syria is unknown. Sometimes science can be very complicated and its results difficult to interpret.

Communism was a century-long experiment that failed, as measured by the deaths of tens of millions of its own citizens. The division of North and South Korea over half a century ago was an experiment whose results we can see from space: one is dark and impoverished while the other is bright and flourishing. We can learn from such experiments, which is why Thomas Jefferson called democracy an experiment, as when he wrote in 1804:

No experiment can be more interesting than that we are now trying, and which we trust will end in establishing the fact, that man may be governed by reason and truth.

One of the hallmarks of science is its openness to criticism and the freedom to challenge any and all ideas. That is why our founding fathers also insisted on free speech and a free press, because this daring new political experiment depended on unconditional open access to knowledge and the freedom of its citizens to see and to think for themselves.

President Trump, I urge you to consider the words of a great American who helped to make our nation the most powerful on earth. J. Robert Oppenheimer was the head of the atomic-bomb building Manhattan Project, and in 1949 he proclaimed:

There must be no barriers to freedom of inquiry. There is no place for dogma in science. The scientist is free, and must be free to ask any question, to doubt any assertion, to seek for any evidence, to correct any errors. Our political life is also predicated on openness. We know that the only way to avoid error is to detect it and that the only way to detect it is to be free to inquire. And we know that as long as men are free to ask what they must, free to say what they think, free to think what they will, freedom can never be lost, and science can never regress.

Watch the Speech