Karl Popper argued that the defining feature of scientific theories is falsifiability—the possibility, in principle, of being proven wrong. By this criterion, he excluded Marxism and psychoanalysis from science, arguing that their adherents could explain away any contradictory evidence. Critics of Popper note that even core physics theories aren't immediately abandoned when contradictory evidence appears; scientists typically search for alternative explanations first.
Based on the passage, it can be inferred that
Popper believed Marxism and psychoanalysis were scientific
physics theories are never questioned or revised
defining the boundaries of science may be more complex than any single criterion can capture
all scientists immediately abandon theories when facing contradictory evidence
Correct Answer: C
Choice C is the best answer. Popper's criterion has limitations critics point out.
- Context clues: Popper's single criterion (falsifiability); critics note even physics doesn't follow it strictly.
- Meaning: If the criterion doesn't fully describe actual science, demarcation is more complex.
- Verify: The existence of valid criticism shows the issue isn't fully captured by one rule.
💡 Strategy: When a proposed criterion faces valid objections, infer the phenomenon is more complex.
Choice A is incorrect because Popper "excluded" them from science. Choice B is incorrect because the criticism is that physics theories aren't "immediately abandoned"—not that they're never revised. Choice D is incorrect because scientists "search for alternative explanations first."