The idea of necessary connection

Class notes for 20 January

Main points

1.3.14 is where Hume tries to answer the central question that he set for himself: what is our idea of necessary connection an idea of?

Different things that he wrote in that section suggest different answers. In particular, twentieth-century philosophers have tended to take Hume’s claims about what we mean when we think or talk about causes as having one of two dramatic consequences: either we mean that causes are just constant conjunctions of ideas plus a feeling of determination or we mean nothing at all when we attempt to think and talk about causes.

I tried to suggest that this is not what Hume is likely to have meant. The epistemological and ontological positions he would have been committed to stand at odds with the text.

That leaves a question, though: what is our idea of necessary connection? I said that the only plausible possibility, in my opinion, is that the idea of necessary connection is a “faint image” of the feeling that we have when making the transition from one perception that resembles a pair of perceptions that were constantly conjoined in the past to an idea that resembles the other member of the pair.

How we got here

Part 3 is about knowledge and belief. Reasoning, a process by which we come to have knowledge (at least), involves finding relations among ideas. Of the seven philosophical relations among ideas, the causal relation is special, so the rest of part 3 is about it.

The science of man is an attempt to explain as much of our thinking as possible. In order to explain our thoughts about the causal relation, Hume thought that he had to explain the idea of necessary connection. We distinguish between coincidences (every day the sun rises, Green does not go to China) and causes (every time I hit the glass hard with a hammer, it breaks). In the latter case, we think there is a connection between the two objects of our thought (hitting the glass, the glass breaking) that is not present in the first case (sun rising, Green not in China). But what is our idea of that connection?

Hume took a circuitous route of looking at how we draw particular causal inferences in order to figure out how to characterize the idea of necessary connection. 1.3.14 is where Hume tries to give the answer.

Revisionism vs. Eliminativism

Heidi asked why some of the passages on the “Meaning” handout were under the “Elimination” heading instead of the “Revisionism” heading. Here is what I had in mind.

There really isn’t a distinction between the texts that support that Revisionist and Eliminativist readings. Rather, how you read the passages depends on whether you think that the mental substitute for the idea of necessary connection among objects is adequate, that is, whether it is really an idea of necessary connection as opposed to a little trick that our minds play on us.

After all, a feeling of determination of the mind is a poor substitute for causal relations among objects. If you think Hume was saying that the most that we can mean when thinking and talking about causes is that we had a feeling of a certain sort, then I can see why you would think he ruled out all thoughts about causes as meaningless. Hume himself distinguishes between feeling and thinking (Abstract, paragraph 5), so you might think that if he put something in the ‘feeling’ category, he meant to take it out of the category of meaningful thoughts.

In any event, Heidi’s question convinced me that breaking the passages into two like that was misleading. Having thought about it, perhaps it would have been better to put the passages first and then list the three possible interpretations. That has the added virtue of not leaving the last one without any passages at all. Any thoughts would be most welcome.

What the idea of necessary connection is

I hit a point that was so subtle that it may well be non-existent right when most of us were tired and figgedty and the photographer had driven everyone to distraction. Including me.

So I’m going to take another shot at it here. Wish me luck.

Why the idea has to be simple

Hume flailed about when characterizing the idea of necessary connection. Sometimes, he described necessity as being something in our minds; other times, he described the idea of necessary connection as the idea of the determination of our thoughts.

Neither characterization is relevant to what he was trying to do, namely, explain our idea of the necessary connection among objects.

I said that it seemed to me that the reason for the flailing is that he had set himself an impossible task. He tried to explain what our idea of necessary connection is an idea of, the idea of necessary connection has to be a simple idea, and you can’t say what a simple idea is an idea of.

The idea has to be a simple one. Here’s why. Hume states multiple times that we have no impression of necessary connection and concludes that we have no idea of it. But it is possible to have a complex idea without a corresponding complex impression: that’s how I can have the complex idea of a unicorn despite never having had a sensory impression of a unicorn. So the idea of necessary connection has to be a simple one in order to fit into that pattern of argument: no impression, therefore, no idea.

That means that the “no impression, so no idea” argument boils down to: we have no simple impression of necessary connection.

But we do have an idea

However, we do have an idea of necessary connection and there is an impression for it to come from. Impressions are feelings and there is a feeling: the feeling of determination that we get when making the transition from one perception that resembles a pair of perceptions that were constantly conjoined in the past to an idea that resembles the other member of the pair.

An idea is a “faint image” of an impression. The idea of necessary connection is a faint image of that feeling. That’s all it can be, I think.

The subtle part

Here is the subtle part. So subtle that the distinction I am about to try to draw may evaporate. So don’t let me get away with anything here. Here’s what we have from the above.

  1. There is no impression of necessary connection.
  2. There is an impression from which the idea of necessary connection is copied.

The idea of necessary connection is a fainter feeling. It is not an idea of something else. That is the only way I can see of reconciling those two positions.

Here’s another way to put it. Compare the idea of necessary connection with the idea of a standard mid-sized physical object such as my chair. For the idea of the chair, there are three things:

  1. The chair.
  2. The visual impression of sensation of the chair.
    (To be completely accurate, we would have to add in tactile impressions too. I think we can leave out olfactory and auditory impressions as it doesn’t smell or make noises, to me at least, though the cat probably smells it and other critters might hear it. How all of these impressions are put together as impressions of one thing is a question for part 4).
  3. The idea of the chair. This is a faint image of the impression of the chair.

For the idea of necessary connection, there are only two things:

  1. The feeling that we get when making the transition from perception A to idea B, where perception A resembles one member of a pair of perceptions that have been constantly conjoined in the past and idea B resembles the other member of the pair.
  2. The idea, the “faint image,” of that feeling.

There isn’t anything for either the impression or the idea to be of: they’re both just feelings (in whatever sense an idea of a feeling is a feeling, that is). If that seems unsatisfactory, remember that it’s a simple idea.

As a simple idea, there is no saying what it is an idea of beyond pointing back to the impression that it is derived from. The same is true of the other simple ideas. What is an idea of red an idea of except, well, red?

By contrast, complex ideas can be broken into parts that can be described. My idea of a chair is the idea of a piece of furniture with legs and a platform large enough and placed at a suitable height to sit on.

The next problem

This leaves another question, though: why do we think that this idea is relevant to objects? That is, why do we think we have an idea of the necessary connection among objects? Hume tries to solve that problem by saying that we project the feeling onto objects (1.3.14.27).

It is not clear that this makes any sense and we will start with that on Tuesday.