## Devlin's Angle |

Within the past eighteen months, math has even made its
way into the movies, with two feature films in which not
only was the lead character a mathematician, but we even see
mathematics portrayed on the silver screen: *Good Will
Hunting* and *Pi.*

What's going on here? Math in the movies? Is this the start of a trend? How long before we go to a film and there's a quiz at the end?

I jest, of course. The popular association of math with quizzes
is one that I have split much writer's ink -- and several
hours in radio and television studios -- trying to overcome. But
why *did* the writers of *Good Will Hunting* and
*Pi* make their lead characters mathematicians?

*Good Will Hunting,* written by Matt Damon and Ben
Affleck, who both starred in the film, is a Hollywood feel-good movie
about the problems involved in moving from one social world
to another, brought about by being born with an unusual ability.
The hero, Will Hunting (played by Damon), has to have a
precocious talent that can surface without any formal training and
which the audience will regard as completely incomprehensible,
which makes math the number one pick.

*Pi,* shot on a tiny budget by first-time director Darren
Aronovsky in grainy black-and-white, much of it using a shaky
hand-held camera, is a dark, brooding, Kafka-esque film about
the human obsession to find order in the universe, especially
scientific and religious order. Mathematics is the discipline
above all that tries to find perfect order in the world. Hence the
lead character -- he's hardly a hero in the conventional sense --
is a mathematician. (Much of the universe's order involves the
mathematical constant pi, of course, which gives the movie its title.)

In each film, the director had to include sufficient mathematics
to establish the characters. The mathematics shown on
screen in *Good Will Hunting,* though correct, is deliberately
chosen to be unfamiliar to the audience, and is not explained.
Viewers are *supposed* to be baffled. In
*Pi,* on the other hand, the mathematics shown has to
connect to the audience's own (possibly distant) memories of
mathematics, and remind them that mathematics involves
finding formulas that describe order in the world, formulas
that often involve pi. (The familiar formula for the area of a circle
is given considerable prominence at one point.)

Math in the movies is unusual, but *Good Will Hunting*
and *Pi* are not the first films to include some
mathematics. In the 1980 romantic comedy *It's My Turn,*
for instance, star Jill Clayburgh plays a college math professor,
and the film opens with her lecturing to a graduate
mathematics class. She proves a well known (to mathematicians!)
theorem of homological algebra. It's all correct. The
point of having Clayburgh's character be a mathematician is
simply to establish Clayburgh as a highly intelligent
intellectual. Math plays no other role in the film (unless you
include the eternal triangle).

Going back to 1971, Dustin Hoffman's character in *Straw
Dogs* was also a mathematician. Again, the mathematics
shown on the blackboard at one point is the genuine article
(gravitational equations on that occasion). And, as with *It's
My Turn,* the aim is to establish Hoffman's credentials as
an intellectual -- in his case, as an expert in a field generally
regarded as having nothing to do with personal violence.
(The director was Sam Peckinpah, so you can guess what
kind of ending that film has.)

In the 1992 movie *Sneakers,* starring Robert Redford,
a pair of freelance spies battle foreign agents for a powerful
code-breaking chip. As the film makes clear, modern security
codes depend on lots of heavy duty mathematics. At one
point, we see the chip's inventor lecturing on the mathematics
behind its design. Again, it looks right, as it should, given that
one of the world's leading experts on the mathematics of
cryptography was an advisor on the film.

In the movie *Contact* (1997), based on the novel by the
late Carl Sagan, star Jodie Foster makes a good job of
defining prime numbers for a bunch of Washington bigwigs,
and explaining why primes provide a good way to
communicate with intelligent aliens. (Pi would be better.)

*The Mirror Has Two Faces* (1996) shows math
professor Jeff Bridges explaining the Twin Prime Conjecture
(there are infinitely many pairs of primes only two apart, such
as 3 and 5 or 11 and 13) to English professor Barbra
Streisand.

In a little known 1995 film called *Antonia's Line,* a
chronicle of five generations of women, we see Antonia's
granddaughter Theresa grow from being a child prodigy to
become a professional mathematician, who, with unfortunate
stereotypical coldness, prefers to lecture on cohomology and
read research papers on differential geometry rather than
nurse her baby. (All the real-life mathematician mothers I know
would do both.)

Finally, let's not forget *Stand and Deliver,* the excellent
1987 dramatization of the real-life story of the late Jaime
Escalante, an inspired math teacher who managed to teach
calculus to a class of socially deprived, Hispanic high school
students in riot torn South Central Los Angeles. This is really
about math teaching rather than math, though for most
people (apart from mathematicians) the two are the same.

As the lead character says in *Pi,* mathematics is about
identifying and analyzing patterns. What, if any, pattern can
we see in the inclusion of mathematics in movies?

Apart from films such as *Sneakers,* where the plot
brings in mathematics automatically, the most common
attraction seems to be the very fact that, for most people, math
is so incomprehensible. This immediately sets the
mathematical character apart in terms of intellectual ability.
The audience expects the mathematician to do clever things.
The problem facing the director is to show the audience the
mathematician at work in a credible way that intrigues at the
same time as it baffles.

Do *Good Will Hunting* and *Pi* really indicate a new
Hollywood trend, where all the leading stars will clamor to play
the role of a mathematician? Will we see Clint Eastwood eyeball a
young student along a stick of chalk and growl "Go on, prove my
theorem." Somehow, I doubt it. Looking back over all those other
films involving a mathematician, I suspect that what we witnessed
of late was merely the familiar bunching of a random
sequence. But who knows? In any event, I'll give my two thumbs
up to the idea of having more mathematician movie heroes -- for the
simple reason that mathematicians should not be the only group
*not* represented in the movies.

Going back to my original question: Movies apart, why the sudden popular interest in mathematics? In true mathematics instructor fashion, I'll leave that as an exercise for the reader. I'll give my answer in next month's column. Let me know what you think, and I'll try to include some views that differ from mine. (Experience tells me there will be no shortage of those!)

** - Keith Devlin **

Devlin's Angle is updated at the beginning of each month.