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.

As per Mayo's perspective, which of the following best defines the phrase 'scientific explanation'?

• A. One which is most detailed in its explanation of natural phenomena.
• B. One which has been thoroughly tested by scientific experts.
• C. One which survives examinations better than other explanations.
• D. One which refutes other explanations convincingly.

Hint:

Recall what makes a test 'severe' in Mayo's sense, and think about which option matches that, not just detail or volume of testing.

Answer 1

The Correct Option is D

Step 1: Recall Mayo's definition of a severe test.
The passage states Mayo's central idea directly: a claim is only borne out by experiment if it has passed a severe test, one it would be unlikely to pass if it were false. In the Snell's law example, several older laws survived a rough test alongside the true law; only a test severe enough to fail the false laws while the true law still passes would count as validating the true law.

Step 2: Work out what this means for a 'scientific explanation'.
Under Mayo's view, a scientific explanation is not defined by how detailed it is, nor by how many people tested it, nor even by simply surviving one round of testing. What matters is whether the test was strong enough that it would have ruled out, or refuted, every plausible rival explanation had that rival been the true one. A good scientific explanation is one that stands after every likely alternative has been checked and knocked out.

Step 3: Rule out the other options.
Option 1, most detailed, is not Mayo's criterion at all, being detailed says nothing about whether rival explanations were tested and eliminated.
Option 2, thoroughly tested by experts, sounds close, but Mayo's criterion is not just about who tests it or how much testing happens, it is specifically about whether the test could have caught the claim being false. A great deal of testing under loose conditions, like the rough Snell's law experiment, still fails Mayo's bar.
Option 3, survives examinations better than other explanations, is closer still, but surviving better than rivals is not the same as actively ruling those rivals out through a severe test; a weak test can let several rivals survive equally well, as the Snell's law example shows.
Option 4, refutes other explanations convincingly, captures Mayo's actual bar: a scientific explanation earns its status by passing tests that would have convincingly disproved it, and by extension the rival explanations, had it been false. This lines up with the passage's description of a severe test.

Step 4: Final Answer.
Since Mayo's criterion is about a test strong enough to rule out rival explanations, not just detail, expert involvement, or comparative survival, the correct answer is option 4. \[ \boxed{\text{Option 4}} \]