APSA Teaching and Learning Conference, February 20, 2005
Draft. Please do not cite without permission.
Beyond the Runaway Trolley:
Thought Experiments in Political Theory
Eric Beerbohm
Department of Politics
Princeton University
Political philosophy – like philosophy writ large – makes liberal use of thought
experiments, hypothetical cases constructed to elicit intuitive responses. This is true
not only as a claim about the dominant methodology deployed by political
philosophers; thought experiments also function as essential pedagogical devices.
They offer dramatic, meticulously paired down cases that force students to report
their pre-philosophical judgments. One leading philosopher describes the classroom
value of so-called intuition pumps:
One might say that intuition pumps are the enduring melodies of
philosophy, with the staying power that ensures that they will be
remembered by our freshmen, quite vividly and accurately, years after
they have forgotten the intricate contrapuntal surrounding argument
and analysis…Intuitions pumps are powerful pedagogical devices.
1
There is much to be said for the virtues of thought experiments in the classroom
setting. We present imagined cases as stories, which are often as memorable as they
are puzzling. A dramatic presentation can counter a lack of imagination,
defensiveness, and intellectual laziness.
My aim here, however, is cautionary. I note a range of hazards that
accompany thought experiments commonly used by political philosophers. The first
section offers a basic taxonomy, drawing largely on contemporary theoretical work.
Along the way, I raise methodological difficulties that attach to each of three types
of thought experiments. The second section identifies a unifying assumption behind
the methodology on which thought experiments are based. The worry, as I see it, is
that appeals to widely shared intuitions can be empirically suspect.
Neither section, however, should be understood as calling for us to put aside
this enduring device. If our aim is to offer ways of organizing our moral intuitions
1
Daniel Dennett, Elbow Room, pp. 17-18.
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