Thought Experiments

Thought experiments are a common methodology to present evidence and to promote reasoning in science classrooms (i.e., to promote evidence-based reasoning). Thought experiments are one of many ways of promoting evidence-based reasoning in the classroom. Other instructional strategies include:

  • wet labs: having students complete experiments in a laboratory or field-work setting

  • demonstrations: having teachers (and/or students) complete experiments in front of others

  • lab exercises: pencil and paper work where some components of a laboratory report are to be completed

  • field work: where teachers and students leave their classroom to visit the outside world

See the CRYSTAL Alberta website for a more complete list of evidential bases that might be used in the classroom.

For thought experiments:

  • the understanding comes through reflection on the situation

  • methodology is based on logic rather more than on empirical evidence

  • well structured hypothetical questions employ "What if?" reasoning

  • diagrams and hand-waving are common (to replace actual experimentation)

Consequences of thought experiments include:

  • challenging (or even refuting/falsifying) an accepted concept

  • confirming/verifying an accepted concept

  • establishing/creating a new concept

Examples of thought experiments include:

  • Newton's cannon

  • Galileo's leaning tower of Pisa experiment

  • Van Helmont's experiment

The above summary is presented in more detail in the files that are attached below. Check them out. Also see the teacher-education lesson plan for thought experiments and for evidential bases.