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Critical Rationalism Epistemology Explanations

I discussed epistemology in a recent email:

I really enjoyed David Deutsch's explanation of Popper's epistemology and since reading Fabric of Reality I've read quite a bit of Popper. I've become convinced that Deutsch's explanation of Popper is correct, but I can also see why few people come away from Popper understanding him correctly. I believe Deutsch interprets Popper in a way that is much easier to understand.

Yes, I agree. DD refined and streamlined Critical Rationalism, and he's a better writer than Popper was. Popper made the huge breakthrough in the field and wrote a lot of good material about it, but there's still more work to do before most people get it.

Plus, I think he actually adds some ideas to Popper that matter that make it less misleading. Popper was struggling himself to understand his own theories, so it's understandable that he struggled to explain some parts of it.

I agree. I don't blame Popper for this, since he had very original and important ideas. He did more than enough!

(For example, it was problematic to refer to good theories as 'improbable' rather than 'hard to vary.' In context, I feel Popper meant the same thing, but the words he chose were problematic for conveying the meaning to others.)

So I've been wondering if it's possible to boil Popper's epistemology (with additions and interpretations from Deutsch) down to a few basic principles that seem 'self evident' and then to draw necessary corollaries. If this could be done, it would make Popper's epistemology much easier to understand.

Here is what I've come up with so far. (I'm looking for feedback from others familiar with Popper's epistemology as interpreted and adjusted by Deutsch to point out where I got it wrong or are missing things..)

Criteria for a Good Explanation:

1. We should prefer theories that are explanations over those that are not.

This is an approximation.

The point of an idea is to solve a problem (or multiple problems). We should prefer ideas which solve problems.

Many interesting problems require explanations to solve them, but not all. Whether we want an explanation depends on the problem being addressed.

In general, we want to understand things, not just be told answers to trust on authority. So we need explanations of how and why the answers will work, that way we can think for ourselves, recognize what sort of situations would be an exception, and potentially fix errors or make improvements.

But some problems don't need explanations. I might ask my friend, who is good at cooking, "How long should I boil an egg?" and just want to hear a number of minutes without any explanation. Finding out the number of minutes solves my cooking problem. I didn't want to try to understand how cooking eggs works, and I didn't want to debate the matter or check my friend's ideas for errors, I just wanted it to come out decently. It can be reasonable to prioritize what issues I investigate more and which I don't.

2. We should prefer explanations that are hard to vary over ones that can easily be adjusted to fit the facts because a theory that can be easily adjusted to fit any facts explains every possible world and thus explains nothing in the actual world.

Hard to vary given what constraints?

Any idea is easy to vary if there are no constraints. You can vary it to literally any other idea, arbitrarily, in one step.

The standard constraint on varying an idea is that it still solve (most of) the same problems as before. To improve an idea, we want to make it solve more and better problems than before with little or no downside to the changes.

The problems ideas solve aren't just things like "explain the motion of balls" or "help me organize my family so we don't fight". Another important type of problem is understanding how ideas fit together with other ideas. Our knowledge has tons of connections where we understand ideas (often from different fields) to be compatible, and we understand how and why they are compatible. Fitting our knowledge together into a unified picture is an important problem.

The more our knowledge is constrained by connections to problems and other ideas, the more highly adapted it is to that problem situation, and therefore the harder it is to vary while keeping the same or greater level of adaptation. The more ideas are connected to other problems and ideas, the less wiggle room there is to make arbitrary changes without breaking anything.

Fundamentally, "hard to vary" just means "is knowledge". Knowledge in the CR view is adapted information. The more adapted information is, the more chance a random change will make it worse instead of better (worse and better here are relative to the problem situation).

There are many ways to look at knowledge that are pretty equivalent. Some ways are: ideas adapted to a problem situation, ideas that are hard to vary, non-arbitrary ideas, ideas that break symmetries (that give you a way to differentiate things, prefer some over others, evaluate some as better than others, etc. You can imagine that, by default, there's tons of ideas and they all look kinda equally good. And when two ideas disagree with each other, by default that is a symmetric situation: either one could be mistaken and we can't take sides. Knowledge lets us take sides it helps us break the symmetry of "X contradicts Y, therefore also Y contradicts X" and helps us differentiate ideas so they don't all look the same to us.)

3. A theory (or explanation) can only be rejected by the existence of a better explanatory theory.

Ideas should be rejected when they are refuted. A refutation is an explanation of how/why the idea will not solve the problem it was trying to solve. (Sometimes an idea is proposed as a solution to multiple different problems. In that case, it may be refuted as a solution to some problems while not being refuted as a solution for others. In this way, criticism and refutation are contextual rather than universal.)

You don't need a better idea in order to decide that an idea won't work – that it fails to solve the problem you thought it solved. If it simply won't work, it's no good, whether you have a better idea or not.

These are fairly basic and really do seem 'self evident.' But are they complete? What did I miss?

I then added a number of corollaries that come out of the principles to explain the implications.

1. We should prefer theories that are explanations over those that are not.
a. Corollary 1-1: We should prefer theories that explain more over those that explain less. In other words, we should prefer theories that have fewer problems (things it can’t explain) over ones that have more problems.

Don't judge ideas on quantity of explanation. Quality is more important. Does it solve problems we care about? Which problems are important to solve? Which issues are important to explain and which aren't?

Also, we never need to prefer one idea over another when they are compatible. We can have both.

When two ideas contradict each other, then at least one is false. We can't determine that one is false by looking at their positive virtues (how wonderful are they, how useful are they, how much do they explain). Instead, we have to deal with contradictions by figuring out that an idea is actually wrong, we have to look at things critically.

b. Corollary 1-2: We should prefer actual explanations over pseudo-explanations (particularly explanation spoilers) disguised as explanations.
c. Corollary 1-3: If the explanatory power of a theory comes by referencing another theory, then we prefer the other theory because it’s the one that actually explains things.
2. We should prefer explanations that are hard to vary over ones that can easily be adjusted to fit the facts because a theory that can be easily adjusted to fit any facts explains every possible world and thus explains nothing in the actual world.
a. Corollary 2-1: We should prefer explanations that have survived the strongest criticisms or tests we have currently been able to devise.

Criticisms don't have strengths. A criticism either explains why an idea fails to solve a problem, or it doesn't.

See: https://yesornophilosophy.com and http://curi.us/1595-rationally-resolving-conflicts-of-ideas and especially http://curi.us/1917-rejecting-gradations-of-certainty

Popper and DD both got this wrong, despite DD's brilliant criticism of weighing ideas in BoI. The idea of arguments having strengths is really ingrained in common sense in our culture.

b. Corollary 2-2: We should prefer explanations that are consistent with other good explanations (that makes it harder to vary), unless it violates the first principle.
3. A theory (or explanation) can only be rejected by the existence of a better explanatory theory.
a. Corollary 3-1: We should prefer theories (or explanations) that suggest tests that the previously best explanation can’t pass but the new one can. (This is called a Critical Test.)
b. Corollary 3-2: It is difficult to devise a Critical Test of a theory without first conjecturing a better theory first.
c. Corollary 3-3: A theory that fails a test due to a problem in a theory and a theory that fails a test due to some other factor (say experimental error) are often indistinguishable unless you have a better theory to explain which is which.

Yes, after a major existing idea fails an experimental test we generally need some explanatory knowledge to understand what's going on, and what the consequences are, and what we should do next.


Elliot Temple on July 17, 2018

Comments (2)

I read this article on Kindle, via Send to Kindle app and I couldn't differentiate the quotes from normal text, they appear the same.


Anonymous at 2:36 PM on July 19, 2018 | #10332 | reply | quote

Sounds like Kindle is completely broken. They are standard html blockquote tags.


Anonymous at 2:39 PM on July 19, 2018 | #10333 | reply | quote

What do you think?

(This is a free speech zone!)