Question

Deborah Mayo is a philosopher of science who has attempted to capture the implications of the new experimentalism in a philosophically rigorous way. Mayo focuses on the detailed way in which claims are validated by experiment, and is concerned with identifying just what claims are borne out and how. A key idea underlying her treatment is that a claim can only be said to be supported by experiment if the various ways in which the claim could be at fault have been investigated and eliminated. A claim can only be said to be borne out by experiment, and a severe test of a claim, as usefully construed by Mayo, must be such that the claim would be unlikely to pass it if it were false.

Her idea can be explained by some simple examples. Suppose Snell's law of refraction of light is tested by some very rough experiments in which very large margins of error are attributed to the measurements of angles of incidence and refraction, and suppose that the results are shown to be compatible with the law within those margins of error. Has the law been supported by experiments that have severely tested it? From Mayo's perspective the answer is 'no' because, owing to the roughness of the measurements, the law of refraction would be quite likely to pass this test even if it were false and some other law differing not too much from Snell's law true. An exercise I carried out in my school-teaching days serves to drive this point home. My students had conducted some not very careful experiments to test Snell's law. I then presented them with some alternative laws of refraction that had been suggested in antiquity and mediaeval times, prior to the discovery of Snell's law, and invited the students to test them with the measurements they had used to test Snell's law; because of the wide margins of error they had attributed to their measurements, all of these alternative laws pass the test. This clearly brings out the point that the experiments in question did not constitute a severe test of Snell's law. The law would have passed the test even if it were false and one of the historical alternatives true.

Which of the following conclusions can be drawn from the passage?

• A. Experimental data might support multiple theoretical explanations at the same time, hence the validity of theories needs to be tested further.
• B. Precise measurement is a sufficient condition to ensure the validity of conclusions resulting from an experiment.
• C. Precise measurement is both a necessary and sufficient condition to ensure the validity of conclusions resulting from an experiment.
• D. Precise measurement along with the experimenter's knowledge of the theory underpinning the experiment is sufficient to ensure the validity of conclusions drawn from experiments.

Hint:

Think about what the Snell's law example proves about rough measurements and rival theories, rather than about what precision alone can guarantee.

Answer 1

The Correct Option is A

Step 1: Identify what Mayo's idea actually claims.
The passage explains that a claim is only 'borne out' by an experiment if the experiment is a severe test, meaning the claim would be unlikely to survive the test if it were actually false. The Snell's law example shows that a rough experiment, with wide margins of error, lets several rival laws, including ones known to be wrong, pass the same test as the true law. So rough measurement cannot tell a true law apart from a false one.

Step 2: See what this implies about experimental results in general.
If wide error margins let multiple, mutually exclusive laws all appear consistent with the same data, then a single experiment's data can end up supporting more than one theoretical explanation at once. The passage's whole point is that we cannot simply trust that an experiment has confirmed a theory, we must keep checking, through severer tests, whether rival explanations have truly been ruled out.

Step 3: Check each option against this.
Option 1 says data can support multiple explanations at once, so theories need further testing, this is exactly the Snell's law example: several old, false laws passed the same rough test as the true law, and only a more severe test would separate them. This matches the passage closely.
Option 2 says precise measurement alone is sufficient for valid conclusions. The passage never claims precision by itself is enough, it only says imprecision is a problem, not that precision guarantees a correct conclusion.
Option 3 goes further and says precise measurement is both necessary and sufficient, but the passage nowhere argues that being precise is enough on its own, only that a severe test, which usually needs precision, is required.
Option 4 adds the experimenter's theoretical knowledge as a further sufficient condition, but the passage does not discuss the experimenter's knowledge of theory at all, so this option brings in an idea the passage never raises.

Step 4: Final Answer.
Since options 2, 3, and 4 all overstate what precise measurement alone can guarantee, and option 1 is the only one that matches the passage's actual warning about multiple explanations passing the same test, the correct answer is option 1. \[ \boxed{\text{Option 1}} \]