Evaluating Explanations - Adequacy

Every branch of knowledge has its own specific guidelines for evaluating the adequacy of explanations in that area, but there are also some general standards that apply across the board.

1. The inference from hypothesis to explanandum should have a high degree of logical strength.

2. The explanation should be complete: it should explain all significant aspects of the explanandum.

3. The explanation should be informative: the hypothesis should state the fundamental cause or reason for the explanandum.


Comprehension Questions

1 Identify the standard that the explanation given below violates.

The nurse must be guilty because more people died on his shift than any or the other ones.

a) The explanation lacks logical strength.
b) The explanation is incomplete.
c) The explanation is not informative.
d) The explanation lacks consistency.
e) The explanation lacks simplicity.
f) Some predictions made by the explanation are not true.
2 Identify the standard that the explanation given below violates.

A library received a book back marked through and through with red ink. When she wrote the person who last checked it out, she received a reply stating that she could not have written in the book because she did not have a red pen. The reply was written in red ink.

a) The explanation lacks logical strength.
b) The explanation is incomplete.
c) The explanation is not informative.
d) The explanation lacks consistency.
e) The explanation lacks simplicity.
f) Some predictions made by the explanation are not true.
3 Identify the standard that the explanation given below violates.

It was once thought that margarine was better than butter because it did not clog the arteries like butter does. However, it has been found that trans fatty acids, which are found in margarine, may clog arteries the same as butter does.

a) The explanation lacks logical strength.
b) The explanation is incomplete.
c) The explanation is not informative.
d) The explanation lacks consistency.
e) The explanation lacks simplicity.
f) Some predictions made by the explanation are not true.
4 Identify the standard that the explanation given below violates.

Each time a cell divides, its daughter cells have less telomere. However, a single-cell organism that lives in ponds does not suffer from telomere decay, because it has a telomere-preserving factor.

a) The explanation lacks logical strength.
b) The explanation is incomplete.
c) The explanation is not informative.
d) The explanation lacks consistency.
e) The explanation lacks simplicity.
f) Some predictions made by the explanation are not true.
5 What criticism is being raised of an explanation in this passage?

A clock gene similar to that found in worms with extended life-spans was found in humans, and it was suggested that if this gene could be re-set, the human life span could be significantly increased. However, up to 7,000 more genes might be peripherally involved in the aging process.

a) The explanation lacks logical strength.
b) The explanation is incomplete.
c) The explanation is not informative.
d) The explanation lacks consistency.
e) The explanation lacks simplicity.
f) Some predictions made by the explanation are not true.
6 Identify the standard that the explanation given below violates.

Your theory that you were actually transported through space to another place in the universe light-years away cannot be sustained. The more likely explanation is that extreme stress caused by the malfunction in the spacecraft caused you to hallucinate, thereby leading you to believe that something which did not occur actually did.

a) The explanation lacks logical strength.
b) The explanation is incomplete.
c) The explanation is not informative.
d) The explanation lacks consistency.
e) The explanation lacks simplicity.
f) Some predictions made by the explanation are not true.


Evaluating Explanations - Truth

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