Welcome to the second lecture on David Hume.
A brief reminder of what we looked at last time.
We looked through some of Hume's early philosophical interests, as witnessed by various evidence, including letters, both of whom and others.
Contemporaneous records, some notes that Hugh made that are now in the National Library of Scotland,
which gave indications about where some of his early interests were and in particular looking at the book,
one of the treaties his first published work and the emphasis that he puts there on causation.
And we saw that there was a pretty plausible narrative about how Hume came to have the interests that he did.
And that particular focus, we've got a nexus of topics centred around causation, all of vivid interest to Hume at an early point in his life.
And the suggestion is that one of the main drivers of the philosophy in book one of the treaties is Hume's ambition to apply logic and concept
empiricism to the notion of causation and in particular the necessity that he sees as characteristic of causation and armed with that tool,
the lockey and empiricism. He is going to attempt to deal with some of these issues.
OK, so let's now proceed through the treaties broadly in the order that Hume does,
and we'll be paying more attention to some parts and less to others.
But where we skip over stuff, I will be referring to it and giving a brief summary.
So we're going to look at Hume's theory of ideas and this is book one, part one.
Very important parts of the book because it sets the scene for much else.
It's actually quite short, but it's packed full of relevant theory.
So humour dots, what standardly called the theory of ideas, and this is seen as emerging really with Descartes,
but Hume's version of it is inherited largely from John Locke.
So Locke's essay concerning human understanding I mentioned this last time and giant of a book towered over the philosophy in the following century,
and Locke defined an idea as whatsoever is the object of the understanding when a man thinks.
So ideas are supposed to include all types of thinking, including perception and feeling, as well as contemplation.
So what Locke calls ideas include both thoughts and sensations and also internal ideas that we get from reflection.
Now, Hume looks at Locke's distinctions and says this, this actually isn't very helpful,
it's not very useful to use the word ideas to cover the whole lot.
So I Hume, I'm going to draw a distinction within Locke's category of ideas and distinguish between what I shall call ideas, proper and impressions.
So an impression is either a sensation. Or a feeling so a sensation could be from seeing the sky, I see the sky.
I get an impression of blue. I smell a flower. Maybe I kick my foot and I feel pain.
That's a physical sensation. So those are all impressions.
On the other hand, if I think about the sky, close my eyes, think about the blue of the sky.
Think about the pain. Think about the existence of God. Those are all ideas.
And Hume uses the word perception where Locke used the word idea, so a perception for Hume covers both impressions and ideas.
Now, importantly, Hume, like Locke, thinks that there are two different sources of impressions and therefore ideas.
Obviously, Locke calls these sources of ideas. Hume calls them sources of impressions, but then the impressions give rise to ideas.
Impressions are of two kinds those of sensation and those of reflection.
So impressions of sensation, not surprisingly, are impressions that come from the senses, colours, smells, pains.
But other impressions arise from things that we think or reflect about.
So suppose I think about a pain that I previously experienced that might make me fearful about encountering countering the same pain again,
that fear the feeling of fear is itself an impression.
I might think of somebody who's had some extraordinarily good luck, and I might, as a result, feel envious.
So that feeling of envy is an impression of envy. And these are impressions of reflection, which, according to human, are either passions or emotions.
Now I want to draw here an important contrast with Locke.
This isn't explicit at all. It's not something that Hume even seems to recognise.
But I think in understanding Hume, it helps to realise that he's got a particular focus,
which actually, in some parts of his philosophy, arguably leads him astray.
So here is Locke in his essay Talking About Reflection.
So just like him, he draws a distinction between sensation and reflection.
Sensation is a source of ideas from the senses externally.
Reflection is where we contemplate our own minds and we get impressions from that.
I'm using here Hume's terminology of impressions, where Locke called them ideas,
but the the crucial difference between them is quite different from that.
By reflection, says Locke, I mean that notice,
which the mind takes of its own operations by reason whereof they come to be ideas of these operations in the understanding.
Such are perception, thinking, doubting, believing, reasoning, knowing, willing and all the different acting's of our own minds.
Now. Look at that list.
Lock is clearly focussing on operations of our minds, we look into our minds and we see ourselves thinking, we see ourselves knowing and willing.
But Hume says impressions of reflection are either passions or emotions.
So Hume seems to be completely overlooking the operations that Locke is focussing on,
and Locke seems to overlook the kinds of feelings that Hume is focussing on.
So this is well worth noticing.
It actually leads him into a little bit of trouble light later because he overlooks some of the kinds of impressions that Locke is focussing on.
OK, what's the difference between impressions and ideas? Well, Hume Hume's text gives the impression.
Sorry about the use of the word impression here.
But if you read Hume's text, it will seem to imply that the the defining difference between impressions and ideas is one of fulsome vivacity.
All the perceptions of the human mind resolve themselves into two distinct ideas, which I shall call impressions and ideas.
The difference betwixt these consists in the force and liveliness with which they
strike upon the soul and make their way into our thoughts or consciousness.
Those within which enter with most force and violence, we may name impressions.
Well, that seems relatively straightforward, but immediately, Hume notes a problem for this view in sleep,
in a fever, in madness or in any very violent emotions of soul.
Our ideas may approach to our impressions,
and it sometimes happens that our impressions are so faint and low that we cannot distinguish them from our ideas.
Now, that seems very odd if the defining difference between impressions and ideas is false and vivacity, then how could it ever be?
There's an idea could achieve sufficient force and veracity to be confused with an impression,
and one can imagine easily enough impressions that will be lacking in vividness, for example, watching paint dry.
That's an impression you're seeing the paint, but it's not very vivid.
On the other hand, imagine that you think of being attacked by spiders.
For many people, that would be extremely vivid, but you're not actually perceiving anything.
Now you might be able to try to get around this.
You might say, Well, what Hugh means is that the impressions are more vivid than the corresponding ideas.
So that really being attacked by spiders would be more vivid than just having an idea of it?
Maybe. But on the face of it, Hume seems to be trying to draw this general distinction in terms of false and vivacity,
and he himself is pointing out that there are problems with it.
I think actually it's best to understand Hume's distinction between impressions and ideas as basically the distinction between feeling and thinking,
I believe it will not be very necessary to employ many words in explaining this distinction.
Every one of himself will readily perceive the difference between feeling and thinking.
So don't think of the and vivacity criterion as definitive of the distinction between impressions and ideas.
Impressions and ideas are actually to be understood in terms of the mental operations.
Is it a matter of sensation or feeling or is it, on the other hand, a matter of thinking and the former impressions?
The latter ideas generally corresponds to false and vivacity, but false and vivacity is not definitive of the distinction.
But why, then, does Hume put such an emphasis on false and vivacity?
Well, if we look a little bit later in the treaties and we'll be coming to this later to treaties one three seven six,
that's book one, part three, section seven, paragraph six, we'll be using that kind of reference lot.
The same idea can only be varied by a variation of its degrees of force and vivacity.
Now, this is related to his empiricism. He wants to say that all our ideas are derived from impressions.
Now, that means he's got to have a close correspondence between impressions and ideas.
Their content has to be the same. If the one I copied from the other.
But then if the contents the same, won't they be identical? Well, no, because they can vary in fulsome veracity.
So and veracity is the term Hume uses when he wants to say that one mental item is has the same content as another,
but is nevertheless somehow different. So the difference between a mere idea and a belief?
What's the difference?
Well, a belief is a more vivid idea, but it has to be the same idea because otherwise it wouldn't be a belief of the same thing.
So it will come to that later.
Another point here again, which we'll see with his theory of belief, is that Hume has a sort of hydraulic theory of force and vivacity.
He wants to say that some of the operations of the mind are to be explained in terms of force and vivacity moving between our various perceptions.
So a very vivid perception of something can occur, can deliver force and vivacity to an idea.
So when I see something, I get an impression of it.
The force and vivacity from that impression can transfer to associated ideas and elevate those ideas into beliefs.
So this is why Hume puts that emphasis on fulsome vivacity.
Now, I'm not generally going to be discussing these views of him from a philosophical perspective, criticising them.
But I do want to draw attention to a general problem with the theory of ideas.
And it can seem a very tempting way of thinking about the operations of the mindset.
It was very tempting to a lot of philosophers in the 17th, the 19th century.
But I want to highlight a risk. If if you think in terms of our thoughts or our sensations indeed involving ideas in front of the mind,
then the risk is that it makes the mind seem rather passive. The mind is just sitting there perceiving these various impressions and ideas,
and the activity of the mind is to be understood in terms of these various perceptions that occupied the stage.
Now, that doesn't seem to be very faithful to how the mind works.
The mind is active. It's not just having a sequence of perceptions going in front of it.
And moreover, our mental activity is not usually best understood in terms of queasy perceptual states.
It's, I might have say, the image of a of a dog in front of my mind, let's say.
And that might be accompanied by lots and lots of different kinds of thinking, I might be thinking,
I wish I had a dog or I must remember to take the dog for a walk, or I wonder how the dog is now or my dog is rather small.
Or you could. There are endless different thoughts that one could be having associated with a single image.
And the idea that mental activity can be pinned down purely in terms of the perceptions in front of the mind seems to be a very simplistic.
So I've spelt that out a little bit more. We'll see.
Incidentally, that the same issue comes up a little bit when Hume discusses personal identity.
He actually warns against the idea of thinking of the mind as a mental stage.
He actually goes to the extent of thinking of the self of simply consisting of bundles of perceptions that avoids one problem,
but it falls into another anyway. Of that more later. So let's get a word now about lock and the origin of ideas.
So I'd stress that Hume is following Locke's empiricism. And Locke was arguing against people like Descartes.
I mean, particularly Descartes, because Descartes claimed that we have certain innate ideas.
Two of those the innate idea of God. Those, you know, the trademark argument from the third meditation.
Descartes actually appeals to this idea that he has of God.
And he says it's such a perfect idea it must have had a perfect source.
The only possible source for this idea is God. So it's an innate idea that's been given to me by God as a sort of trademark.
The idea of extension for Descartes is an innate idea.
He thinks that by looking at our idea of extension, we can draw conclusions about the way the physical world works.
Now, John Locke wanted to oppose that.
He wanted to argue that all of our ideas come from experience in book, one of the essay concerning human understanding.
He argues against innate principles. If you like innate knowledge of those arguments, I think are rather problematic for various reasons.
Far more emphasis historically has been given to book two of the treaties sorry,
book two of the essay where Locke goes through a whole catalogue of different ideas and shows how they could arise from experience.
So the main influence of Locke's attack on Descartes was to provide an alternative
account of how various ideas which made the hypotheses have been neatness redundant.
And this was extremely influential, most philosophers following lots,
particularly in Britain, took something like Locke's empiricism more or less for granted.
So as I say, Lock is an empiricist about ideas.
Hume's copy principle, which we're coming to in a moment, is essentially a reworking or reformulation of locks empiricism.
But first, we've got to draw a distinction. Because it's not true that all of our ideas are directly derived from experience.
And the reason for this is some ideas are complex, they're made out of parts and having acquired ideas of the parts,
we can construct new ideas by putting those parts together in novel ways.
So take an Apple. Well, the idea of an Apple you might get by pondering an apple in front of you and smelling it, tasting it,
that Apple has a shape, a colour, a taste or smell, and we can distinguish those and the shape.
Indeed, the shape of an apple is a complex shape. So we can distinguish different parts within it.
And having taken apart the various bits, we can put them back together in different orders.
So one example that uses is the idea of a golden mountain.
I've got the idea of a gold mountain, but I haven't got that idea from an impression of a Golden Mountain.
I've never seen a Golden Mountain, but I have had impressions of a mountain and I have had impressions of gold.
And I can put those together and form the I put the ideas derived from those impressions together and form the idea of a gold mountain.
Likewise, I've seen a banana. So I've got the impression of a banana.
Therefore, the idea of a millionaire, the shape of the banana.
And I can put that together with the idea of the taste of an apple and come up with a new concept like an apple,
a banana shaped fruit that has the taste of an apple.
OK, now at Treaties one one, three four. Hume talks about the liberty of the imagination that is our ability to cut up our ideas into simple parts,
mix them, make new complexes and to do that more or less arbitrarily.
He calls that his second principle. The second principle of the liberty of the imagination.
And it comes back at treaties one one, seven three.
And I'll have I'll be saying a little bit about this later. Later, the so-called severability principle.
The odd thing is that when he comes back to the severability principle, he says,
We have already seen this principle and it looks like the only place he can be referring
to there is one one three four where he talked about the liberty of the imagination.
OK, so Hume divides all ideas and impressions into simple and complex,
simple perceptions or impressions and ideas such as admits of no distinction or separation,
the complex of the contrary to these and may be distinguished into parts and in the treaties.
At least he seems to treat this as an absolute distinction.
Certain ideas are absolutely simple. Certain ideas are absolutely complex, and any complex idea can be divided up into symbols.
In the enquiry that 1748 the book one of the treatises 1739 in the enquiry.
He's less explicit about the distinction. It may be that he's less confident in it.
We just don't know. He does mention simple. He does mention complex, but he never draws the distinction in quite the same way.
So it's possible that he's having doubts about the absolute simplicity or complexity of ideas.
And one reason why he might have had such doubts will come to shortly.
OK, so now having drawn the distinction between simple and complex ideas.
Now Hume can state his coffee principle.
All our simple ideas in their first appearance are derived from simple impressions, which are correspondent to them and which they exactly represent.
OK, so a complex idea like the idea of a unicorn.
Doesn't necessarily get derive from a conflict, a corresponding impression.
But it's made up of part in this case, a horse and a horn, which are, of course, themselves complex.
But those ideas I have derived from complex impressions.
And what I'm saying is that wherever you get an idea, no matter how complex it is,
ultimately it must be derived from ideas that have been copied from impressions.
OK. Now, Hume acknowledges his debt to lock in two places,
and he actually seems rather uncritical about the coffee principle he's arguments for it are not particularly strong,
as we'll see the obvious explanation. Why he seems to take it relatively for granted is precisely that it is when humans writing lock and orthodoxy.
In fact, the coffee principle is probably best known from the enquiry rather than the treaties.
And there he seems to weaponize it when we entertain any suspicion that a
philosophical term is employed without any meaning or idea as he's about to frequent,
we need but enquire from what impression is that.
I suppose the idea derived and if it be impossible to assign any, this will serve to confirm our suspicion.
This is a very famous passage. And if you look at this, you would get the idea that what humans going to do is to explore various supposed ideas.
He's going to examine them and say, from what impression is that supposed idea derived, there is no impression from which it could be derived.
Therefore, it's a bogus idea. Throw it in the bin. That's the impression you get from the enquiry.
In fact, he hardly ever does that. He does it a little, but nearly always.
What Hume is doing is pursuing the impressions from which ideas are derived, not in order to debunk the ideas, but actually to shed light on them.
OK, so Hume gives two arguments for the coffee principle.
The first argument is that there aren't any counterexamples to it.
If you look through all the different ideas in your mind,
you will find that all of them can be resolved in two simple ideas that are derived or were derived from simple impressions.
And we find from experience that the impressions come before the ideas,
so it follows that the impressions must cause the ideas rather than the other way round.
OK, so. Give them this exact correspondence.
It's reasonable to infer that the one they're closely related.
Second argument, people who lack any particular sense modality lack the corresponding ideas.
A blind person, for example, can't have the idea of read.
A deaf person cannot have the idea of the sound of a trumpet.
They can't get the appropriate impressions. And we find they don't have the ideas.
The obvious explanation is that the idea is to derive from the impressions, and that's why they lack the ideas.
But actually, these arguments are not particularly strong. First of all, suppose somebody disagrees with him.
Suppose somebody says, actually, I have got some ideas that aren't derived from impressions.
I mean, for example, the idea of the self, the idea of substance, the idea of inheritance, the idea of a vacuum.
How's your market going to argue against them because humans are if Hume's argument is actually look at all your simple ideas,
you will find they're always derived from simple impressions. Then his opponent just denies that and said, sorry, you're begging the question.
It's so it's not really on for him to say, I look at all my own ideas, I find there are no exceptions.
You're claiming an exception, but you must be wrong because there aren't any exceptions. That's just begging the question.
Just by the way, Don Garrett does attempt to defend him on this,
and I will be providing you with a reading list to cover the various people that I'm mentioning as we go through to give the other side as it were.
But certainly Hume himself doesn't defend his arguments at any length, he states it in a very cursory form.
What about the second argument? A blind man can have no idea of red.
Is that true? How would you know? How could we possibly know whether a blind man has the idea of red?
You ask him, do you have the idea of red, red? What's red?
Well, it's a colour. What's a colour? Something you see what? See?
Well, I don't really know how to explain it to you. I guess you just don't have the idea.
But how do we know he might do it? Simple, simply because he's blind.
He can't actually identify things in the world that are red, so we can't know whether he's experiencing the idea of red.
That doesn't prove that in his mind, he doesn't have the idea.
So again, we've got an argument that seems rather weak.
Now some authors, Bennett Decker, for example, have tried to defend him here and say,
actually, what Hume is really doing here is not giving a claim about the mental entities,
the perceptions in our mind, but really, we should understand him as talking about meaningfulness of words.
The problem for the blind man is that he cannot use the word red in the way that we use it because he has no access to public means of verification.
Well, maybe. I mean, I think it's fair to see this kind of positive positive is thinking.
I mean, the sort of thing logical positive is in the 20th century we're keen on.
I think you can see that sort of forces inherited from Hume, but it seems to me rather implausible to really take Hume himself as arguing in this way.
So it is possible to say Hume's on to something here.
Maybe he's got a germ of a philosophical insight, and he's expressing that in the rather limited vocabulary that's available to him.
But here we're going to carry on discussing things in Hume's limited vocabulary in order to understand and thinking.
OK, so let's put the basis of the copy principle behind us.
As I've said, Hume himself probably takes it pretty much for granted because it was so much of the lock in orthodoxy.
But strangely, immediately after he's enunciated the poppy principle, he himself raises a difficulty for it.
The famous missing shade of blue. So the idea is imagine that I have in my life been I've seen lots and lots of different shades of blue.
But there's a particular shade of blue that I've never seen.
And imagine that all the shades of blue that I've seen are lined up kind of in a spectrum, but with a gap where the missing shade is.
And the question is, could I, as it were, create for myself the idea of that missing shade?
And Hume actually thinks plausibly I could I could sort of blend the shades on either side and form an idea of the missing shade.
But he then immediately after having raised this, he says, OK, maybe we can have a simple idea,
namely the simple idea of that particular shade of blue, which isn't derived from a corresponding impression.
But this is such a singular in that particular example. Let's not worry about it.
That seems a little bit odd. I actually think he could.
He can easily justify putting it to one side.
One reason is that the new idea is clearly being constructed.
But from ideas that have been derived from experience, so it's actually not a serious violation of Locky and empiricism.
Moreover, it's an idea that you could derive from sensory experience, even though I haven't derived it that way.
It is a possible idea that could be derived from a straightforward visual impression.
So it's not a particularly problematic idea. But.
Notice that if you does take the strategy here that I've suggested,
it might undermine the absolute distinction between a simple, simple and complex ideas.
Because if an idea, if a simple what Kim thinks of as a simple idea can be created from other simple ideas by blending.
Then there's a sense in which on this occasion, that's a complex idea because it's being constructed from others.
So he may not be able to maintain the straightforward, simple, complex distinction.
OK. I've already mentioned that the theory of ideas is somewhat problematic because it parses our thinking in terms of ideas in front of the mind.
Another point is that because of his empiricism, Locke takes ideas to be straightforward copies of impressions,
which means he tends to conceive of our thinking in a very imagistic way.
And he tends to think of mental severability when we divide ideas and then put them back together almost as though, you know, we're using Photoshop.
So chop this idea here. This one here put them together in new ways.
A lot of his thinking is very much focussed on a visual metaphor.
And that, combined with the copy principle, explains some of the crude as he was thinking about the mind.
And as I've said, he has a rather impoverished view of the faculty of Reflection.
OK, so let's move on to the Association of Ideas and the Theory of Relations.
I'll be saying more about the theory of relations next time here.
I just want to kind of introduce it in situ and say a little bit about it.
OK, now he's already introduced the principle of the liberty of the imagination.
That is, we can take our ideas. We can chop them into bits.
We can move them around, put them together in new ways and we can do that almost arbitrarily.
Nevertheless, when we're thinking our ideas do not move arbitrarily, they move in patterns.
So if, for example, we're daydreaming, our thoughts may go through different things.
You know, I look at a picture and I think that guy, he looks rather like so-and-so, that guy.
He had a nice house that was next door to, oh gosh, and they had a terrible fire.
And now my mind is wandering from one thing to another, and it's moving partly on the basis of resemblance.
I look at that guy and he reminds me of someone else, and then I contiguity. His house was close to such and such.
Cause and effect there was a fire and that had various impacts.
And humans claim is that whenever our ideas move from one thing to another in this sort of way,
it's either based on resemblance or contiguity, you know, with closeness in space or time and cause and effect.
So there are three associative relations the qualities from which this association arises.
Of three, this resemblance contiguity in time or place and cause and effect.
And he likens this to Newtonian gravity.
He suggests the Association of Ideas may be as big in the theory of the mind as gravity has proved to be in the theory of the physical world.
So there are various places.
Another is in the abstract to the treatise right at the end, where he really waxes lyrical about the Association of Ideas.
And we'll see later on in the treaties that he appeals to the association to explain a lot of mental phenomena.
OK, but at this point, Hume seems to be very committed to being systematic.
He's now introduced complex ideas, he's introduced Association of Ideas, and now he's going to talk about the different kinds of complex ideas.
They may be divided into relations modes and substances. Just before moving on to those categories, however, let's draw a clear contrast with Locke.
This is Locke discussing the Association of Ideas.
This sort of madness, this weakness to which all men are so liable, a taint which so universally affects infects mankind.
There is a connexion of ideas wholly owing to chance or custom ideas that in themselves are not
at all of keen come to be so united in some men's minds that it is very hard to separate them.
So notice previous philosophers and lot wasn't the only one prior to whom for Association of Ideas was a source of error.
The fact that we associate one idea with another that our ideas naturally link together in this in this tempting way leads us astray.
It leads us into superstition and all sorts of ridiculous views. So this is a very, very strong contrast.
Hume is going to emphasise association of ideas as what enables us to think about the world at all.
So he's got a much, much more positive view than the philosophers that came before him.
OK, so he was going through the various complex ideas and he starts off, you know,
relations modes and substances, actually, relations proves to be the most important of those.
And as I said, I'll be saying more about the theory of relations next time where it becomes really important.
But increases one one five humans just introducing the theory of relations.
And it starts off in a way that can seem a little bit confusing, but he's actually, I think, very straightforward.
You've got a distinction between two different senses of the word relation.
OK, so suppose I say that this building the examination schools is related to Salisbury Cathedral.
Oh, really? How is it related? Well, Salisbury Cathedral is bigger and older, and it's about 75 miles away.
Hang on. That's not a relation. That doesn't make them related.
Well, in one sense, it does, right in the philosopher's sense, it does.
You can disdain, you can say X and Y have the following relation X is bigger than Y and older than Y and about 70 miles away.
That constitutes a relation that can hold between different pairs of objects.
But that's not the kind of relation that's going to naturally make your thought go from one to the other.
So in the ordinary, everyday sense, we wouldn't say they're related in the ordinary, everyday sense.
We say that things are related when thinking of one of them naturally leads your thoughts to thoughts of the other.
Yeah, and that's when they are linked by contiguity or resemblance or causation, according to him.
OK, so there's a difference between the natural and the philosophical view of relation.
And Hume is more interested in philosophical relations. He wants to look at relations in the philosopher's sense.
And here I'm just going to very quickly say that his theory of relations here is highly, highly derivative from locks.
So if you look at Locks essay, he categorises various types of relation like this.
And we can line them up against the various kinds of relation that Hume identifies.
So notice that what Hume does. He takes the theory of relations that Locke has presented, and he says all the philosophical relations,
all the different kinds of relations that philosophers recognise can actually be shoehorned into seven different categories.
OK. So resemblance, cause and effect, space and time identity, contrary to proportions in quantity, degrees in quality.
So this will become important in the next lecture.
OK, I'm going to finish with a quick survey of the last part of book one, part one, which is Hume's theory of abstract ideas.
Now, how important this is to understanding Hume is a controversial matter.
Some scholars, notably Don Garrett, thinks that Hume's theory of general ideas actually informs a huge amount of his philosophy that there are lots of
human claims which can only be properly understood when understood in the light of the theory of general ideas.
My own view is somewhat in contrast with that.
I suspect that Hume introduces this theory because he sees that something he has to deal with here.
And he introduces what he thinks is a plausible way of dealing with it.
But I think when he's discussing other topics later on, he largely forgets it.
That's to say that that's an open question. Or I think, you know,
Don Garrett has done a lot of work to to argue that certain of Hume's theories really do make better sense when seen in this light.
And I'm not going to discuss that controversy at this point.
Now, first of all, let's let's look at the general problem here. I'm an empiricist, is claiming that all of our ideas derive from impressions.
So all of our ideas ultimately come from sense, experience or feelings.
But what about general ideas? I mean, I can have the idea, say, of a particular person by seeing them see someone, I form the idea of them.
But how can I form the idea of a person in general because I never see a person in general, I only ever see specific people.
So quite generally, I'm an empiricist, has this problem.
How do we explain where general ideas come from?
Well, Locke's theory. Is that ideas become general by separating from them the circumstances of time and place and any
other ideas that may determine them to this or that particular existence by this way of abstraction?
They are made capable of representing more individuals than one,
each of which having in it a conformity to that abstract idea is, as we call it, of that sort.
OK. Let's see that applied to a particular example.
The ideas of the person's children converse with. Unlike the persons themselves, only particular.
OK, so we only see particular people. The idea is that we form from them our particular ideas.
The names they first give to them are confined to these individuals, nurse and mama.
Afterwards, they observe that there are a great many other things in the world that resemble their father and mother.
They frame an idea which they find those many particulars du partaken and so that they give the name man.
Here he clearly means person. Wherein they make nothing new, but only leave out of the complex idea they had of Peter and James,
Mary and Jane, that which is peculiar to each and retain only what is common to them all.
OK, so the child sees lots of different people recognises that there are things in common between them
and then forms an idea which includes all the common bits and leaves out all the specific bits.
And that gives them the general abstract idea of a person.
OK, that seems to be Locke's theory. That's certainly the way Berkeley and Hume interpreted it.
And a notorious example of this is Locke's triangle.
He gives the example of the idea of a triangle which has to be neither oblique nor
rectangle nor equilateral a quicker rule that means isosceles nor scaling on.
But all of these none of these at once. So in order to form an idea of a triangle which somehow is applicable to all triangles,
I've got to form an idea which has what is in common to all triangles, but leaving out whatever is specific to them.
And not surprisingly, George Barclay comes along and attacks this and says you cannot form any such idea.
This is an impossible idea. How can you possibly have an image of a triangle which is neither scaly nor
isosceles nor equilateral any right angled and not right angled at the same time?
Forget it. It's hopeless. And Berkeley gives a rival account of abstract ideas, which I think is best understood by example.
So take this famous example of a geometrical proof.
So we've got a triangle here and a line has been drawn from the the right hand vertex of the triangle parallel to the left hand side.
And now we can see that the left hand angle of the triangle is identical to this angle here.
You can't see my cursor, unfortunately, this angle here and their corresponding angles.
And you can see that the top angle of the triangle is the same as the top angle here.
There alternate angles.
And we can therefore conclude that some of the three angles to the truck of the triangle is the same as the angles on a straight line.
OK. Famous proof now that's been proved about a specific triangle.
But we can see that the way we've been thinking about that triangle could apply to any other triangle.
All right. You could change the angles, you could move the lines along.
And as long as you form basically the same construction, the same conclusion is going to follow.
So here we are, using a single particular triangle as an exemplar, and we're using it to reason about all triangles, whatever.
And Berkeley says that's how our ideas work. We use specific ideas and reason with them as exemplars.
We don't somehow form this lucky and abstract idea, which is all triangles and none of them at once.
We reasoned with specifics that interpret them as general.
So very briefly, I just want to mention it's not clear that Berkeley is being fair to lock here.
OK, this scholarly controversy about exactly how lock should be interpreted.
But there are passages in lock which suggests that he may well be thinking of things in exactly the way the Berkeley is.
OK, maybe Berkeley misinterpreted him. By the way, neither Berkeley nor Hume are particularly faithful at interpreting Locke.
Do not get your lock scholarship from Berkeley or Hugh.
They are rather opinionated and in certain topics like this one rather keen to put the boot in.
OK, back to then.
Hume credits Berkeley with this great and valuable discovery that all general ideas are nothing but particular ones annexed to a certain term,
which gives them a more extensive signification and makes them recall upon occasion other individuals which are similar to them.
In fact, Berkeley hasn't put that much emphasis on the certain term that comes from Hume.
But Hume's theory of abstract ideas or general ideas is very much like Barclays, except that he puts this great emphasis on use of a term and custom.
When we found a resemblance amongst several objects,
we apply the same name to all of them after we've acquired a custom of this kind the custom of applying a name,
say the word dog to that dog and that dog and that dog and that dog.
The hearing of that name, dog revives the idea of one of these objects.
So when I hear the name dog, I think of one of these dogs and makes the imagination conceive it with all its particular circumstances and proportions.
So I'm conceiving of a very particular dog. But as the same word is supposed to have been frequently applied to other individuals,
the word not being able to revive the idea of all these individuals only revives that custom, which we have acquired by surveying them.
They are not really present to the mind, but only in power. We keep ourselves in a readiness to survey any of them.
So when I hear the word dog, although a particular idea of dog comes into my mind, nevertheless, the word dog,
because it's customarily associated with a whole load of other dogs, kind of has a power there to revive the ideas of those dogs at appropriate times.
And Don Garrett is called this the revival set of ideas.
That's a nice term. So after the mine just produced an individual idea upon which we reason the attendant
custom revive by the general abstract term readily suggests any other individual,
if by chance, we form any reasoning that agrees not with it.
So let's suppose my mind go when the word dog appears.
My mind goes to a particular dog. You know, well, I'm very fond of a minute.
Somebody says all dogs are friendly. Well, at that point, although I'm thinking of that friendly dog,
my mind is naturally drawn towards other dogs associated with the custom that aren't friendly.
And because I I am aware of other dogs that aren't friendly, those come to my mind and make me realise that the claim all dogs are friendly is false,
even though it was true of the particular dog that I was thinking of the the the fierce
dogs that I've come across in the past jump into my mind and replace the previous idea.
So essentially, humans theory of of general ideas has the term, the word playing a very important role.
It kind of binds together the various ideas of dogs as it may be in such a way that
they can potentially fly into our mind at relevant times and inform our reasoning.
OK. He argues against Locke, and I'm not going to go into detail here. Here I'm simply as I will do it,
a number of occasions in these lectures simply give you slides that summarise things so that you can go and read over them for yourselves,
but kind of see the main points. He argues against Locke, so he's supplementing Barkley's arguments.
And as one of these arguments, he introduces what's commonly called the severability principle.
He doesn't call it this, but we shall. And this is where, as I mentioned earlier in the lecture, he's alluding back to the liberty of the imagination.
So let's just look at the severability principle here. We have observed, he says, where did we observe that him?
He must be referring to one one three four. We have observed that whatever objects are different are distinguishable and that
whatever objects are distinguishable are separable by the thought and imagination.
And these propositions are equally true in the inverse. And then what?
Whatever objects are separable are also distinguishable and that whatever objects are distinguishable are also different.
Now, at the moment, that looks perhaps tautology.
It's it's hard to see what is going to draw from this, and it will be much later that we see this principle playing havoc in one part for.
At this stage, Hume's argument for the principle does give the impression that it's pretty much trivial.
But how is it possible we can separate what is not distinguishable or distinguish what is not different?
So we'll come back to that later. There is one problem that Hume notes with his theory of abstract or general ideas.
The severability principle, as just enunciated,
he thinks that implies that we cannot possibly think about a line separately from its length because a line and its length cannot be separated.
It's evident at first sight that the precise length of a line is not different nor distinguishable from the line itself,
nor the precise degree of any quality from the quality.
But then if that's right, it seems to make it impossible to distinguish some of the things that we actually do distinguish, how do we manage that?
Hume and Hume ends his discussion. With what he calls the distinction of reason.
So for basically his answer is if you have a globe of white marble and a cube of white marble,
you can by focussing on the two objects, you can focus on what's common to them that whiteness.
Whilst ignoring what's different between them, namely their shape.
So although actually with the with the globe of white marble,
we can't really distinguish the shape from the colour because what we've got there is is a globe of white and the two are not separable.
The whiteness is globular in shape by comparing with other objects as it might be a black globe or a white cube.
We can focus on what is similar and what is different, and thus draw distinctions which the severability principle might have seemed to rule out.
And that's it for today.
That's where we finish treaties one one we'll be going on mainly to treaties one three with a quick nod, treaties one to next time.
Thank you.