"Counting and waiting are the same"

That's what Joseph Hellerstein said today during his talk at Brown.

While I wait for the bus, I can engage my neighbors if there are any people around me; I can watch the trees, the birds, the traffic; I can turn inwards and focus on a problem I am currently working on. Or I can count while I wait.

Numbers are our friends.

When I was a kid, I used to have high blood pressure whenever the school nurse took my blood pressure. Waiting for her to measure it made me nervous and raised the pressure. But one day I found the secret to low blood pressure: counting. Counting keeps my blood pressure down.

When I am bored, or stressed, or at the dentist's, I count. Which numbers are prime? What are their divisors? Running the Eratosthenes sieve in my head passes the time pleasantly. Numbers are comfortingly familiar. They have a calming effect.

I can also count what I see while waiting. What fraction of the cars passing me have a passenger? How many SUV's? Do the license plates exhibit any discernible patterns? Counting helps the world make sense even when it doesn't.