Updated: 03 March 2000
EXPLANATION – beside intrinsic interest
goal of science ?
theories that have truth or high verisimilitude because they are needed
instrumentalism vs realism
Duhem - science does not explain
contemporary instrumentalism seeks account of explanation that permits
explanation without truth
EXPLANATION : what is it?
Answer to a “why” question.
Why did Adam eat the apple?
Why is the sky dark at night?
Why is the balloon expanding?
answer depends on the context
audience - questions
information available to audience
(why does sodium turn yellow ?)
specification of question
(why do you rob banks?)
apprentice robber of some naivety
ernest young social worker
supposed to give understanding
OED: explanation - “statement or
circumstance that explains”
explain: “to make clear or intelligible”
“to give understanding”
? Explanation = any story that gives understanding
Real vs apparent understanding
The seven heavenly bodies
add in background belief
why – God – mirror - cosmos
Philosophical theory of explanation - an
account of what constitutes genuine explanation in a context.
All things being equal, we seek a single
Covering Law Model
In his book, How We Think,
John Dewey describes a phenomenon he observed one day while washing
dishes. Having removed some glass
tumblers from the hot suds and placed them upside down on a plate, he noticed
that soap bubbles emerged from under the tumbler’s rums, grew for a while, came
to a standstill and finally receded into the tumblers.
Why did this happen? Dewey
outlines an explanation to this effect: Transferring the tumblers to the plate,
he had trapped cool air in them; and thus to an expansion of the soap film that
had formed between the plate and the tumblers’ rims. But gradually, the glass cooled off, and so did the air inside,
and as a result, the soap bubbles receded.
The explanation here outlined may be
regarded as an argument to the effect that the phenomenon to be explained, the explanandum phenomenon, was to be
expected in virtue of certain explanatory facts. These fall into two groups: (I) particular facts and (ii)
uniformities expressible by means of general laws. The first group includes facts such as these: the tumblers had
been immersed in soap suds of a temperature considerably higher than that of
the surrounding air; they were put, upside down, on a plate on which a puddle
of soapy water had formed that provided a connecting soap film, and so on. The second group of explanatory facts would
be expressed by the gas laws and by various other laws concerning the exchange
of heat between bodies of different temperature, the elastic behaviour of soap
bubbles, and so on. While some of these
laws are only hinted at by such phrasings as ‘the warming of the trapped air
led to an increase in its pressure’, and others are not referred to even in
this oblique fashion, they are clearly presupposed in the claim that certain
stages in the process yielded others as their results.
Mill System of Logic 1843
Received View - in empiricist tradition
uses relatively unproblematic
social sciences vs natural
remains point of departure for discussions of explanation
can you solve Hempel’s
See that what happened, had to happed given
other things (the particular facts) because of the laws
See why it had to happen
An explanation is an argument !!!
Initial Conditions: C1, C2,...Ck
Explanadum \ E
1. Argument valid
2. Laws enter essentially
explains importance -
particular events and to
But explanations don’t look like this !
Hempel : “models” … “a useful reminder … explanation as characterized
constitute ideal types or theoretical idealizations and are not intended to
reflect the manner in which working scientists actually formulate their
Why did the butter melt? The pan was still hot.
“an account of this kind omits
mention of certain laws of particular facts which it tacitly takes for granted,
and whose explicit citation would yield a complete deductive-nomological
explanans not detailed enough to entail the specific explanadum
more work needed
Freud explains his slip of the pen due to unconscious desire
need more detail
Why did anyone go to Canada?
Because of the fur trade
general outline to be
area to look for laws
concept of proof in mathematics
“an argument Y is a proof of a given sentence X without making any
mention of persons who might take cognizance of Y”
“… constructing a nonpragmatic concept of scientific explanation - a
concept which is abstracted, as it were, from the pragmatic one, and which does
not require relativization with respect to questioning individuals any more
than does the concept of mathematical proof.”
But is there any such thing?
Idealized audience of Nobel prize winners ?
Better to acknowledge that it is pragmatic
Handle certain objections
All crows are black
Icabod is a crow
Therefore, Icabob is black
fall about laughing at poor old Hempel
Or imagine telling quantum chemistry story to school kids
Logical Space of Explanation
- Hempel avoid subjectivity in
All meet the conditions, pragmatic factors dictate which one it is
appropriate to give
Henry the mad bird painter
Statistical Inductive Explanation
smoking - lung cancer
high probability replaces proof
syphlis – paresis
1The American Objection
sky dark at night
Explanation is asymmetrical
DN Model does not guarantee this.
So not a sufficient condition for explanation.
Accidentally true generalizations do not
What makes a true generalization a law?
But this is a common problem
Icabod fails to get pregnant
Sugar dissolves in holy
DN Model fails to exclude irrelevancies.
barometer falls, bad weather
Can it be done? Dewey’s problem again.
Dewey understood without knowing the laws. Cannot match the laws with
the initial conditions.
Try to fit your favourite explanations into DN form
accept claims as explanatory without checking to see if we can
transform them to DN model
Explanation by models and analogies
for a wide class of cases, to explain is to cite a causally relevant
explanations are not
to explain is to cite a feature of the world which is causally
responsible (partially) for what you want to explain
But what is causation?
must be more than Humean
Explanation by identification
Water is H2O
Temperature is mean molecular
Why did DN seem so good?
Tradition of deductive presentation of knowledge
Models as idealizations
Much of physics - stipulating ideal systems (ideal gases). Derivations (if temperature goes up, so does
Understanding provided if world is sufficiently like the idealization.
Derivation confused with
Models explain by drawing attention to the causal mechanisms.