expected value, philosophy

The Cost of Injustice

A number of reviews of my book Constitutional Calculus object to my quantification of events.  For example, after the events of 9/11, there were suggestions (and there continue to be suggestions) that we round up Muslim-Americans and put them  in internment camps, just like we did to Japanese-Americans during World War II.

Arguments around internment invariably lead to arguments about balancing “civil rights” with “national security,” with “How would you feel if your family was killed by terrorists?” countered with “How would you feel if your family was put in a concentration camp?”

I say, run the numbers.  Mathematically, there are two strategies:  internment, or non-internment.  We can compute the expected value of the two strategies, and use that to decide which to pursue.


  • It costs about $20,000 per year to house one prisoner in federal custody.
  • Wrongfully detained persons are entitled to $50,000 per year of detention.
  • There are 1.5 million Muslim-Americans.

Total cost of internment would be $105 billion each and every year.

Since the federal government would be footing the bill, then we need to compare how much the 9/11 attack cost the federal government.

At this point, we’ll invoke the following philosophy:  We will give the strategy we oppose on whatever basis the greatest possible benefit of the doubt.  In particular:  whenever we make an assumption about our cost-basis, we’ll give preference to those that make the objectionable strategy a better choice.  If, at the end of the day, that strategy is still the worse choice, then we can, with a clear conscience, object to it.


In this case, I find the internment strategy objectionable.  So I’m going to make some wildly generous assumptions about the cost of a 9/11 attack that will make the best possible case for the strategy I don’t like.  So here goes:

  • Cleanup and repair was about $9 billion.  That’s for the Pentagon and municipal cleanup, and not the cost of the World Trade Center buildings.  Those costs were not paid by the Federal Government, and if we are making an honest comparison, we cannot include those costs.  (Even if we’re trying to make the best possible case for internment, we still can’t compare different types of costs without being dishonest)
  • Let’s assume the 3000 dead would have worked for another 20 years.  Here’s a wildly generous assumption:  assume they paid $50,000 each and every year in taxes.  That amounts to another $3 billion in tax revenues lost by the government.
  • Here’s another wildly generous assumption:  The growth rate of the GDP was slower following the 9/11 attacks.  If we attribute all of the decrease to the 9/11 attacks (despite evidence that we were already in a recession at the time), then lost revenues (again, to the federal government) amount to another $90 billion.

Total cost of the 9/11 attack:  $102 billion for each event.

There’s one crucial unknown:  how often do 9/11 attacks occur?  Planning for the actual 9/11 attack took about two years.  Presumably, a new 9/11 attack would take a similar amount of time, if only because the conspirators couldn’t simply cut-and-paste the original plan, and they’d have to confront security measures implemented since the original attack.  Let’s suppose they could put it together in a year.

So if one 9/11 attack occurs each and every year, then the strategy of non-internment costs $102 billion every year.

This means there are three billion reasons why internment is a bad idea.  Actually, the difference is even greater, because we tried to make the best possible case for internment, and made wildly generous assumptions on tax revenue and GDP loss; further, it seems unreasonable to think that a 9/11-sized attack could be executed every year. You don’t need to talk about civil liberties or national security:  the cold equations tell us internment is a bad idea.

Now, you might disagree with the analysis above (and I hope you do, since it would help you develop the habit of knowledge).  Go ahead, find your own numbers.  But the important thing is that you can’t compare apples to oranges:  you have to be consistent, because otherwise the comparison is meaningless.

What of the critics?  Many objected to this type of analysis, because it ignores the pain and suffering of the 3000 dead and their families.  True enough…but that cost isn’t paid by the federal government, while internment would be paid by the federal government.  If you’re going to make an honest comparison of strategies, you can’t compare costs borne by one entity to the costs borne by another.

But let’s go further:  If we wanted to include the pain and suffering of the 3000 dead and their families in the cost tally (economists call this type of thing an externality: thus, the real cost of gasoline isn’t just the price you pay at the pump, but it’s pollution, global warming, and instability in oil producing countries), we could…provided that we also include the pain and suffering the internment of 1.5 million Muslim-Americans would cause.

If you don’t include this, then you are selling their lives for your benefit.  There are many words for that, none of them pleasant.

philosophy, statistics

The Habit of Knowledge

One of the biggest mistakes people make when they finish school is they get out of the habit of knowledge.

Knowledge isn’t about acquiring information.  We gain information anytime we read an article about the antics of the Kardashians.  The problem is that this type of information doesn’t require a human brain:  pictures of Kim will be on the internet forever.

Knowledge is about the habit of wrestling information to the ground, of tracking it down, of verifying and validating it.  If the President claims sanctuary cities are hotbeds of criminal activities, you can either believe this claim…or you can hunt down its source (there is none).

And having found none, you ask yourself the next question:  What’s the real story?  If you do that, you find that the opposite is true:  sanctuary communities actually have lower crime rates, as well as higher median incomes, and lower unemployment.

For more about the mathematics behind this conclusion, you can watch this video:


The Art of Estimation

I have another site, Math for Everyone, which I’d started in because I like to talk about mathematics.  The problem is that as the year moved on, it became clear that what I really wanted to talk about was politics…and how mathematics should play a key role in determining public policy and sentiment.

Because of that, I’m transitioning my more political posts to this one.  But here’s a post from my Math for Everyone site, regarding how to estimate crowd sizes:  The Art of Estimation.


Condorcet’s Dream


This is a portrait of the Marquis de Condorcet (1743-1794).  The Enlightenment was about applying reason, evidence, and logic to society.  Condorcet identified mathematics as the best way to do this.  In his last work, he expressed his hope for the future:

The application of the arithmetic of combinations and probabilities to [moral and political] sciences, promises an improvement by so much the more considerable, as it is the only means of giving to their results an almost mathematical precision, and of appreciating their degree of certainty or probability.

Let us move forward together towards realizing Condorcet’s dream of a society made better by the application of mathematics and evidence.