Thought Experiments in Ethics:
A Contextualist Approach to the Grounding Problem
Researcher: Anne Harland
- Date Complete: 1998/12
- Degree Awarded: Ph.D.
- Research Supervisor: A.D. Irvine
How can an experiment which occurs only in thought lead to new and accurate
conclusions about the world beyond thought? What makes thought experiments
relevant to the domains they are designed to explore?
One answer is that successful thought experiments are grounded. Explaining
the nature of this grounding relationship, especially as it applies to
ethics, is the main task of this dissertation.
A thought experiment is an experiment that occurs in thought. The "thought" label
distinguishes it from an ordinary physical experiment, while the "experiment" label
distinguishes it from other types of merely analogical, conjectural, or
hypothetical reasoning. Many of the components that are necessary for a
successful physical experiment are also necessary for a successful thought
experiment. A thought experiment, like a physical experiment, must isolate
and vary variables in order to answer a question within a given theoretical
context. The result of the experiment has repercussions for its theoretical
The grounding relationship holds between the components of the thought
experiment and the theoretical context of the thought experiment. In order
for the thought experiment to be successful, both the experimental set-up
and our responses to it need to be grounded in the thought experiment's
An experimental set-up will be grounded whenever it meets the following
conditions. The concepts used must be defined normally, dependent and independent
variables must be isolated and relevantly related, and the propositions
of the thought experiment (excepting those describing extraneous particulars)
must be relevantly related to the given theoretical context and the question
Grounding responses to thought experiments will then be largely a matter
of anticipating and disarming distorting influences. Factors influencing
responses include the individual's knowledge of the theoretical context,
the state of development of that context, the nature of the presentation
of the thought experiment, and subjective filters.
It is sometimes difficult to ascertain whether a thought experiment in
ethics is grounded. This is largely due to the nature of the theoretical
context of thought experiments in ethics. In order to assess the relationship
of thought experiments in ethics to their theoretical context, I advocate
employing a contextualist methodology involving the process of wide reflective
equilibrium. While contextualists use this approach to arrive at considered
judgements relating to specific ethical problems, I show that wide reflective
equilibrium can also be used to examine the grounding of thought experiments.
I conclude the dissertation with an examination of the relationship of
thought experiments to computer simulations, a study of various common
thought experiment distortions, and some tests and methods designed to
aid constructing successful thought experiments.