PHL220: Hume's Enquiry, sections IV part 2, and V
Hume's Enquiry, sections IV part 2, and V
Hume, Section IV part 2
- Our reasoning about matters of fact is based on cause and
effect, and our reasoning about cause and effect is based upon
experience - but then, what is the nature of all of our
conclusions from experience?
- These conclusions "are not founded on reasoning, or any
process of the understanding."
- I have found that such an object has always been
attended with such an effect
- I foresee, that other objects, which are, in
appearance, similar, will be attended with similar
- Hume holds that: we do leap from 1 to 2 (we actually find
that we are compelled to leap from 1 to 2), but we have no
reasoning leading from 1 to 2.
- Experience shows us individual instances of experience
- Reasoning about cause and effect draws conclusions based
on kinds of experiences in the future.
- This is not given in reasoning about relations of ideas,
since there is no contradiction in supposing a causal claim
- This is not given in reasoning about matters of fact.
- BUT! All knowledge from matters of fact is based upon
experience, and all experience is based upon reasoning about
cause and effect! So, we cannot appeal to experience to
explain cause and effect.
- Thus, causal reasoning comes down to: we see some
correlation, and we believe it will continue.
- "From causes, which appear similar, we expect similar
effects. This is the sum of all our experimental
Hume, Section V, part 1
- Philosophy can tend to lead to error, when we want our
theories to give us good answers.
- We can avoid making errors about what is unclear by
remaining skeptical when appropriate.
- Our skeptical problem (from Section IV) is: why assume
that there is a special relation between causes and effects?
- Hume gives not a "straight" answer, which would describe
such a special relation, but rather a skeptical solution,
which asserts our lack of any solution but can live with this
- Suppose someone comes fresh into the world: for him all
things are like random events.
- After experiencing the world, he comes to see some
correlations. He begins to assume that one kind of thing
always follows another.
- This is a custom or habit.
- Belief in cause and effect is not based on any feature in
the world, but is rather just a feature of human nature.
"after the constant conjunction of two objects, heat and
flame, for instance, weight and solidity, we are
determined by custom alone to expect the one from the
appearance of the other" (page 28).
"All inferences from experience, therefore, are effects of
custom, not of reasoning" (p 28)
- This is the most compelling argument for the problem of
induction ever given.
An aside about the Problem of Induction
- Hume's Enquiry Section IV gives our first statement of
the problem of induction that we have encounted.
- Section V gives Hume's skeptical "solution" to the
- (Section VII is where Hume completes his account of the
problem of induction, by attacking the notion of a power or
necessity underlying causation.)
- Hume's statement of the problem is the most famous, and
after Hume a number of solutions have been tried.
- The problem of induction
- Hume's formulation: we assume that A causes B and
will do so in the future because we've seen that As
are followed by Bs in our experience.
- Bertrand Russell's restatement: we have no reason
to believe in "the uniformity of nature."
- It must be conceded, to begin with, that the fact
that two things have been found often together and
never apart does not, by itself, suffice to prove
demonstratively that they will be found together in
the next case we examine.
- For example, Russell says, "The only reason for
believing that the laws of motion will remain in
operation is that they have operated hitherto."
- Kant offers one very influential solution: argues that
experience requires cause and effect. Since there is
experience, there is cause and effect.
- A contemporary solution to the Problem of Induction
- Today, another solution is the most widely
accepted: a pragmatic solution.
- The pragmatic solution is based on two ideas
- There are events with dependent,
- Time is not a special variable in testing
- Point 1 says that: The aim of induction is to
find series of events whose frequency of occurrence
converges towards a limit. (Hans Reichenbach)
- A frequency converges towards a limit if it has a
given probability. An ideal coin toss converges
towards 50% heads, for example.
- Point 2 says that being in the future is not
different than being in another place as far as
testing for convergences is concerned.
- Frederick Will's example of the island with
regions called past and future is relevant.
- Will accuses Russell and perhaps Hume of an
implicit mistake: tomorrow, like the old song, is
"always a day away."
- This solution works, BUT it does mean that we
still need to assume one thing: there are phenomena in
the world that are interdependent to some probability
that converges at the limit.
- We have gotten rid of the problem of induction,
if this argument is sound, but we still have a
(perhaps slightly less troubling) "problem": we have
identified something that we must assume, but cannot
prove. We must assume that these converging
- Epistemology may just come down to "you have to
stand somewhere," and the goal then is finding
somewhere reasonable to stand.
- Other solutions to the problem of induction, much less
discussed or even well understood, include Solomonoff's
proof that less complex assumptions are more probable.
Hume, Section V part 2
- Hume argues that belief is a kind of sentiment that we
attach to impressions.
- This sentiment is more commonly attached to stronger
- Impressions are stronger when related to other (strong)
impressions; all such relations are
- When we believe something X, and another thought Y
resembles, is continuous with, or "caused" by that thought X,
then we are more inclined to feel the sentiment of belief for
- Cause and effect then primarily serves to generate in us
sentiments of belief about one thing, given that another thing
we believe occurred before it typically in the past.