Diagramming Explanations

It is rarely, if ever, possible for a single proposition to serve as a complete and adequate explanation of anything. In history, literature, the sciences, or any other discipline, an explanation can involve a highly complex set of propositions.

Explanations are diagrammed in the same way that arguments are. The parts of an explanation can explain the explanandum either independently or jointly. Explanations can have more than one step; in fact, most of them do. Finally, a single hypothesis can support more than one explanandum.

There are two basic questions to ask about an explanation.

First, is it adequate--would the hypothesis, if true, provide a genuine explanation of the explanandum? Does it provide a possible cause or reason, or in some way fit the explanandum into a wider context that makes it intelligible? A good explanation is one in which the explanandum follows from the hypothesis; the relation between them is such that if the hypothesis is true, the explanandum has to be true as well--or at least highly likely.

Second, is the hypothesis true? False premises don't prove anything, and false hypotheses don't explain anything.


Comprehension Questions

1 Which of the following choices best represents the diagram of the explanation given below?

(1) My wrinkles disappeared. (2) The doctor injected the area around the wrinkle with an extract of the deadly toxin that accounts for botulism. (3) The extract caused the muscle to become paralyzed, thus (4) eliminating the wrinkle.

a) 1 supports 2, which supports 3, which supports 4
b) 2 supports 3, which supports 4, which supports 1
c) 4 supports 3, which supports 2, which supports 1
d) 2 and 3 independently support 4, which supports 1
2 Which of the following choices best represents the diagram of the explanation given below?

Investigators are just beginning to piece together the events that led to the tragic ski accident that claimed the life of a young man yesterday. (1) The slopes were slick and the icy patches were not easy to see. (2) The young man killed was very competitive and hated to lose, and, (3) according to the rules, one must pass the ball to another player within 10 seconds. (4) This distracted the skier, (5) causing him to run into a firtree at full speed.

a) 1 supports 2, which supports 3, which supports 4, which supports 5
b) 2 and 3 jointly support 4, which jointly coupled with 1 support 5
c) 1, 2 and 3 jointly support 4, which supports 5
d) 1, 2, 3 and 4 independently support 5


Evaluating Explanations: Adequacy

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