Lecture 3 – Explanation in science
One important aim of science is to try and explain what happens in the world around
us. Modern science is quite successful in its aim of supplying explanations.
Hempel’s covering law model of explanation
Scientific explanations are usually giving in response to the explanation-seeking why-
questions.
Scientific explanations have the structure of an argument
1. Set of premises: tell us why the conclusion is true
2. Conclusion: the phenomenon which needs explaining occurs
After the explanation the relation between set of premises and the conclusion must
be precisely hold in order for the former to count as an explanation for the latter. This
was the problem of Hempel
3 answers to the problem
1. The premises should entail the conclusion – argument should be deductive
2. The premises should be all true
3. The premises should consist of at least one general law (laws of nature)
(example: all metals conduct electricity, a body acceleration varies inversely
with its mass)
So, Hempel’s model of explanation:
General laws + particular facts => phenomenon to be explained
Phenomenon to be explained = explanandum
General laws and particular factors = explanans
The covering law model get is name: for according to the model, the essence of
explanation is to show that the phenomenon to be explained is covered by some
general law of nature.
Hempel drew an interesting consequence from his model about the relation between
explanation and prediction. Whenever we give a covering law explanation of a
phenomenon, the laws and particular facts we cite would have enabled us to predict
the occurrence of the phenomenon, if we hadn't already known about it.
Hempel claimed that every scientific explanation is potentially a prediction - it would
have served to predict the phenomenon in question, had it not already been known.
Hempel also though that every reliable prediction is potentially an explanation.
Explanation and prediction are structurally symmetric.
There are cases that fit the covering law model but intuitively do not count as genuine
scientific explanations. These cases suggest that Hempel’s model is too liberal – it
allows in things that should be excluded. See the 2 examples!
Case (i): the problem of symmetry
Situation A: zie pagina 41!
General laws: Light travels in straight lines
Laws of trigonometry
One important aim of science is to try and explain what happens in the world around
us. Modern science is quite successful in its aim of supplying explanations.
Hempel’s covering law model of explanation
Scientific explanations are usually giving in response to the explanation-seeking why-
questions.
Scientific explanations have the structure of an argument
1. Set of premises: tell us why the conclusion is true
2. Conclusion: the phenomenon which needs explaining occurs
After the explanation the relation between set of premises and the conclusion must
be precisely hold in order for the former to count as an explanation for the latter. This
was the problem of Hempel
3 answers to the problem
1. The premises should entail the conclusion – argument should be deductive
2. The premises should be all true
3. The premises should consist of at least one general law (laws of nature)
(example: all metals conduct electricity, a body acceleration varies inversely
with its mass)
So, Hempel’s model of explanation:
General laws + particular facts => phenomenon to be explained
Phenomenon to be explained = explanandum
General laws and particular factors = explanans
The covering law model get is name: for according to the model, the essence of
explanation is to show that the phenomenon to be explained is covered by some
general law of nature.
Hempel drew an interesting consequence from his model about the relation between
explanation and prediction. Whenever we give a covering law explanation of a
phenomenon, the laws and particular facts we cite would have enabled us to predict
the occurrence of the phenomenon, if we hadn't already known about it.
Hempel claimed that every scientific explanation is potentially a prediction - it would
have served to predict the phenomenon in question, had it not already been known.
Hempel also though that every reliable prediction is potentially an explanation.
Explanation and prediction are structurally symmetric.
There are cases that fit the covering law model but intuitively do not count as genuine
scientific explanations. These cases suggest that Hempel’s model is too liberal – it
allows in things that should be excluded. See the 2 examples!
Case (i): the problem of symmetry
Situation A: zie pagina 41!
General laws: Light travels in straight lines
Laws of trigonometry