Dr. Ari Santas’ Notes on

Hume’s Enquiry V: Sceptical Solution of these Doubts


A.     Moderate Skepticism

·  Hume, in this section, offers a skeptical solution to his doubts about the foundations of causal inference

·  Since he has been branded a skeptic, he wants to explain how his view is not dangerous, but useful

      ·  Hume-s scarlet S in Scotland

·  Hume makes a distinction between extreme skepticism and moderate skepticism, and he claims he upholds the latter

      ·  He is not denying that we can legitimately make causal inference

      ·  He is just refusing to accept the standard account of it

·  He also refuses to believe that we can use causal knowledge outside of common life and practice

·  Hume, like the Academics in Greece, asks us not to doubt everything, but to ground our beliefs in common sense


B.     Common Events

      ·  Causal reasoning involves inferring like effects from like causes, and vice versa

      ·  How is it that we can trust this use of analogy?

      ·  Thrust into the world, we experience sequences of conjoined events

            ·  How is it that we can infer causal connections?

·  I see one event, then another.  How do I know they have anything to do with one another

            ·  Light fuse, firecracker explodes

            ·  Ball hits glass, glass breaks


            Event 1                                     Event 2



              see            do not see                see


      ·  All I observe is the two separate events - how do I know the connection?

            ·  Do not see the force between them

            ·  Cannot get it from reason


C.     Constant Conjunction

      ·  It is clear that we do not just intuit the force like a Cartesian essence       

            ·  If we did, we could make an inference the first time we saw the conjunction

            ·  But we do not

      ·  It is also clear that we do not observe some force connecting the two events

            ·  Again, we would be able to infer after the first occasion

            ·  But we do not

·  What is clear is that after many occasions of observing the like cause and like effect, we come to expect the same in the future

      ·  An observed constant conjunction between similar events gives us the idea of cause


D.     Custom

      ·  At this point, Hume offers his skeptical solution

·  Somehow, our mind forms a habit and becomes accustomed to seeing certain types of events together

·  Given this habit, once we see one event we automatically anticipate the other

      ·  See the ball heading for the glass, imagine the glass breaking (before it does)

      ·  See the broken glass, and the ball, infer the ball came through

·  Custom connects the future with the past

·  Through constant conjunction, we come to associate the relevant ideas, and this is what we call causal connection


E.      Hume-s Foundations

      ·  The consequences are important

      ·  All our knowledge about the world is based on our mind-s ability to form habits

      ·  The source of all our matter of fact reasoning is non-rational

·  Hume-s challenge stands, insofar as he has not given an ultimate explanation of causality

      ·  He only points to a principle of human nature

·  The challenge can be restated:

·  Show me how we can know causes, beyond the fact that we make causal inferences by virtue of a habit

·  The foundation of all causal reasoning for Hume is observation, memory, and habit - all non-rational


Summary of Part I


A.     Customs

·  Hume-s inquiry begins considering the foundation of our knowledge concerning the world

·  It leads him to our use of causal inference

·  Our use of causal inference leads him to question how we can know causal relations

·  That question leads him to experience, which lead him to constant conjunction and custom

·  Custom is the principle which guides out use of causal inference:

·  As the mind perceives conjoined events over and over, it gets into the habit of seeing them together

      ·  As it gets in this habit, given one, it will automatically expect the other


B.     Inference

·  Recall what inference is:  the movement from what we know, to what we did not know

      ·  Or rather, the movement from the present-before-us to the absent-from-us

·  Given X, we infer Y

      ·  Lipstick on the collar?  Adultery!

      ·  Mud on the shoes?  Been in the mud!

·  But to make an inference, you not only need the fact before you, you must also know that that kind of fact is related to another

·  To infer y from x, you need to know that x, and that things of type x are related to things of type y

·  How do we know such relations?

      ·  For Hume, it is custom


Part II


A.     Fiction and Belief

·  Hume here is going to elaborate on his finding: that custom is the governing principle of causal inference

·  He begins by considering the difference between fiction and belief - it has to do with custom

·  We know that the imagination can alter and/or combine any ideas presented to it

·  It can do this in such a way as to produce any ideas as it pleases

·  How is it then, that we can distinguish between what we imagine and reality?

·  In other words, how is it that we can believe certain things and not others?

·  It is not that we glue belief onto ideas, for then we could not believe anything we chose, we cannot

      ·  I can imagine that the chalk will not drop, but I cannot believe it


B.     A Feeling

·  The difference, says Hume, is a feeling or sentiment which accompanies belief, but not fiction

      ·  A feeling is not subject to our will

·  With causal beliefs, for instance, when one object is present to consciousness, the other (its regular partner) is produced by the imagination because of custom, and the idea produced is accompanied by a feeling called belief

      ·  The baseball and the glass

      ·  The chalk falling

·  This is not based on reason, for we can easily conceive of contrary events

      ·  We can conceive it (not by reason)

      ·  We cannot believe it (by feeling)


C.     The Nature of Belief

      ·  Belief is not something we can easily define, if we can at all (sorry Socrates!)

·  Like other feelings such as anger or pain, no verbal account will capture it without the help of experiencing it

·  Luckily for inquiry, we can experience them, and hence describe them

·  Hume will describe belief by introspection

·  What he comes to is basically this:

      ·  Belief is a vivid and steady conception of an object

      ·  It is not in the nature of ideas, but in the manner of presentation

· It is this manner of presentation that helps us distinguish ideas of judgement from fictions in the imagination

·  Belief, then, is an idea presented in such a way that it appears lively and vivacious as if it were an impression


D.     The PreEstablished Harmony

      ·  Hume believes that all belief is fashioned by custom

·  Any time we make an inference about the world, it is because our mind has gotten in the habit of associating two or more ideas

      ·  This principle accounts for all associations of ideas

            ·  Resemblance

            ·  Contiguity

      ·  The pre-established Harmony is this:

            ·  Just as causes and effects are in nature, glued together by forces…

            ·  Ideas are conjoined in the mind by custom

·  Nature struck a good balance here said Hume, for if causation were left to reason and not custom, we would be more likely to fall into error

      ·  Reason is too slow and makes too many errors