The Demarcation Problem
A central question in the philosophy of science is: What distinguishes science from non-science or pseudo-science? This is known as the Demarcation Problem. Solving it is not just a theoretical exercise; it has real-world implications for what we fund, what we teach in schools, and what we trust as evidence in courts.
Verification vs. Falsification
Two major attempts to solve this problem came from the Logical Positivists and Karl Popper.
- Logical Positivism (Verification): A theory is scientific if it can be “verified” by sensory experience. If you can see it or measure it, it’s science.
- Karl Popper (Falsification): A theory is scientific if it is “falsifiable.” It must be possible to imagine an observation that would prove the theory wrong.
Comparison: The Case of Astrology
Consider Astrology.
- Verificationist View: One might argue that astrology is scientific because it often makes “predictions” that seem to come true (e.g., “You will meet someone new today”). Successes are seen as verification.
- Falsificationist View: Popper argued astrology is pseudo-scientific precisely because its predictions are so vague that they can never be proven wrong. “Meeting someone new” could mean a cashier, a new colleague, or a stranger on the bus. No matter what happens, the “theory” remains unscathed.
The “Context of Discovery” vs “Context of Justification”
Regardless of whether one prefers verification or falsification, most philosophers of science distinguish between how a theory is found and how it is judged:
- Context of Discovery: The mess, intuition, accidents, and social biases that lead a scientist to an idea.
- Context of Justification: The logical, objective testing of that idea.
The demarcation criteria usually focus on the Justification. It doesn’t matter if you came up with a theory in a dream; it’s only “science” if it can be justified through empirical testing (Verification) or withstand attempts at disproof (Falsification).
Why Demarcation Matters to Engineering
In engineering, we must distinguish between “rigorous models” and “intuition” or “rule of thumb.” While an engineer might use a heuristic based on years of experience (Tacit Knowledge), the safety of a bridge must be justified through models that are themselves scientific—meaning they are falsifiable and built on verifiable physical laws.