The Demarcation Problem and Falsifiability
Lesson Plan
One of the practical consequences of the Scientific Revolution was a suggestion that one should only believe things that are both true and justified. Eventually, there was even the proposal by mathematician William Clifford that it is morally wrong to believe things without good justification. While early thinkers suggested we need to justify all of our own beliefs, science and the contemporary world are far, far too complicated for each of us to confirm all of our beliefs. We need to have a system to help us decide what is reasonable to believe.
Is chemistry well founded? Astrology? How can we tell the difference between science and what we might call pseudoscience? The stakes are quite high here . . . think about medicine. How can you decide which pills to take to cure your illnesses?
One famous and prominent suggestion comes from Karl Popper: Science as Falsification
See the Discussion Questions tab for questions to help guide this session.
Discussion Questions
- Why is the Demarcation Problem important?
- What does Karl Popper mean by falsifiability?
- What is the difference between saying “we should only believe things which can be falsified” and saying “we should only believe things which are false?”
- Arthur Eddington’s 1919 confirmation of Albert Einstein’s theory of evolution was held by Popper to be a perfect example of a risky claim that made a falsifiable prediction (that is, it laid out the terms under which it would be shown to be false). What does this mean?
- Popper writes “The most characteristic element in this situation seemed to me the incessant stream of confirmations, of observations which "verified" the theories in question; and this point was constantly emphasized by their adherents,” another way of saying that confirming evidence is “cheap” or “easy." What does he mean by this?
- Explain the difference between these two sentences on Popper’s grounds (i.e. the difference between bad science and pseudoscience): “Lightning doesn't strike the same place twice” and “Human psychology is affected by the location of Mars.”
- Is falsifiability falsifiable?
- Is the Demarcation Problem important? Formulate arguments for and against this position.
- Ludwig Wittgenstein, in his work Philosophical Investigations, regularly refers to the concept of language games. He argues that concepts do not need to be clearly defined to be meaningful. Are there some areas between science and pseudoscience that can never be fully determined to be one or the other?
- Darwinian evolutionary theory is the bedrock of modern biology. Is it falsifiable? If not, how is this point significant?
- Are there times we should hold onto some beliefs that fail empirical scientific tests? How can we know whether the hypothesis is false, if the instruments failed, or if something else accounts for this failure?
Resources
This work is licensed under CC BY-NC-ND 4.0
If you would like to change or adapt any of PLATO's work for public use, please feel free to contact us for permission at info@plato-philosophy.org.
Connect With Us!