
The Paradox of Karl Popper - lainon
https://blogs.scientificamerican.com/cross-check/the-paradox-of-karl-popper/
======
trukterious
Popper sounds like a dude. We shouldn't confuse this apparent irascibility
with dogmatism. He was passionate about his ideas: he published them and read
criticism of them. He changed his mind about the testability of evolution, and
other things.

Intellectual humility is not the same quality as personal meekness and
geniuses have always had difficult personalities. Philosophers doubly so. How
could it be otherwise? How can one create new stuff if one is too agreeable
and too susceptible to groupthink?

Btw, the reason falsifiability doesn't have to be falsifiable (by experiment)
is that it isn't a scientific idea; it's a philosophical one. It is
potentially 'falsifiable' by _criticism_ , however.

The best modern Popper proponent is David Deutsch. See his books _The Fabric
of Reality_ and _The Beginning of Infinity_. They're both packed with
interesting ideas and arguments. He says that Popper did indeed solve the
problem of induction. And here's a recent paper of his on the logic of
experimental testing:
[https://arxiv.org/abs/1508.02048](https://arxiv.org/abs/1508.02048)

~~~
raverbashing
> it's a philosophical one. It is potentially 'falsifiable' by criticism,
> however

Agreed. I think the main issue is not with the idea itself of the scientific
method, rather than the practical implications _and its limitations_.

\- The main idea is a qualitative one. It doesn't consider all the statistical
can of worms about reproducibility.

\- Real world experiments rarely reproduce perfectly/exactly. The more the
experiment involves more variables (or unknown variables) you can detect an
effect but its magnitude might vary.

\- Not everything can be reproduced, not everything can be measured perfectly,
hence the "study of knowledge" needs to be able to handle those cases, and not
just bury their head in the sand and go "la la la this is not scientific let's
ignore it"

~~~
jhbadger
What would be a case of actual knowledge that isn't scientific and not
amenable to falsification though? Even humanities like history use evidence
and make conclusions that can be falsified in the light of new information.

~~~
raverbashing
Anything that is limited in observability. Either because the available sample
size is too small, the time or ability to observe something is limited.

A bit of a stretch, but I'm also skeptical of the ability of the scientific
method to be able to understand/prove anything with (hidden) state/memory.

For a lot of 'skeptics' unproven means wrong and unmeasurable means wrong.

------
bo1024
This was a fun read, but I found the premise of the "paradox" frustrating. I
get that it's kind of funny how the falsfiability guy is passionate and
dogmatic about his views. But taking it seriously that this is a contradiction
and asking "is falsification falsifiable" is a basic misunderstanding. It
reminds me of popular misinterpretations of Godel's theorem.

The author seemed to not understand Popper's response, which was dead on of
course. The _type_ of thing that can be falsified is a scientific theory that
makes empirical predictions. Falsification is a prescription for how to do
science. It can be argued against from a philosophical standpoint, but it
makes no predictions and cannot be proven wrong by observation. It's like
asking if the 4th Commandment can be falsified -- the compiler gives a type
error.

Again, enjoyable read, but this aspect was disappointing.

~~~
mactintyre
Nice response; love the 4th commandment point. I found the author to be on the
attack, from the beginning, with the whole taxi driver / address thing. Who
cares? Plus the first driver even knew the street.

Then the author seems pathetic here: "Peering searchingly into my eyes, he
asked if one of his critics had persuaded me to pose the question. Yes, I
lied." Why lie? Have some guts, like Popper evidently does, and believe in
what you want to ask.

Popper at this time was 90 years old, surely not putting his best foot
forward. It was a poor essay overall, IMO, but I love to read anything about
Popper.

------
13415
As far as I remember, that was the worst article about a philosopher that I've
ever read. The author is resentful and pretentious from the start to the end
and tries his best to portray Popper as a kind of silly person.

If you haven't read the article yet, my advice is not to read it.

~~~
ecocentrik
> tries his best to portray Popper as a kind of silly person.

The author seems to have pulled the bulk of the article from 25 year old
notes. He doesn't hide his own youthful naïveté at assuming that a taxi driver
would know directions to the home of a philosopher. He also preserves what I'd
imagine are embarrassing moments like Popper's reaction to his "big question".
What you consider silly, might just be an issue of narrative style.

I personally think it captures the wit and home life of an energetic 90 year
old philosopher. What well adjusted human being doesn't expect to have a
slightly disorganization existence near the end of a very long life?

~~~
jessriedel
> He doesn't hide his own youthful naïveté at assuming that a taxi driver
> would know directions to the home of a philosopher.

Huh? The author specifically asked for directions and was _surprised_ when he
was (unjustifiably) assured he wouldn't need them.

> I personally think it captures the wit and home life of an energetic 90 year
> old philosopher...

13415 isn't saying the author _succeeds_ at making Popper look silly. Rather,
the author is attempting and failing to do so.

~~~
ecocentrik
Taking that assurance at face value was naïve. The taxi thing was a motif. He
frames the interview with it, telling the taxi that picked him up at the end
that a famous philosopher lived there.

> 13415 isn't saying the author succeeds at making Popper look silly. Rather,
> the author is attempting and failing to do so.

How would you define failure in this scenario?

~~~
jessriedel
> Taking that assurance at face value was naïve. The taxi thing was a motif.

You sure do like the word naive!

Do you think he lied about being instructed by the staff member that the taxi
driver would know where the guy lived? If not, then you're arguing that the
author, having been instructed by the staff that he would not need directions,
should have summoned his worldly wisdom and realized this couldn't be true.
But the mere bias of someone's staff, which is of course predictable, does not
explain why that staff would exaggerate in a way that will predictably be
refuted, i.e., when the author gets into the cab, he'll find out they don't
know! So you're arguing that he's naive for not assuming that the staff is
_both_ biased and stupid. But cab drivers knowing where a local minor
celebrity lives is not that crazy of a proposition.

> How would you define failure in this scenario?

Rather than reporting unambiguous (i.e., un-manipulatable) facts that are
clear evidence of silliness, he mostly uses rhetorical techniques which are
completely up to the author's discretion. When he does report facts, they are
completely consistent with Popper being a retired intellectual giant who is
just old, forgetful, and busy. Trying to make Popper look bad because he's a
forgetful 90-year-old comes off as very distasteful.

------
phyller
Ha, I didn't know about him before. Sounds really interesting. Reminds me a
lot of Socrates. I have recently been reading the classics about Socrates and
was surprised to realize that

a) his main mission seemed to be to show people they didn't know as much as
they thought

b) he was basically a huge troll, even if he was usually correct

c) he was such a huge troll that the Athenians actually put him to death for
it via a public trial

If our culture didn't have certain moral qualms that the Athenians didn't have
too much trouble brushing aside, I imagine Karl's career would have been cut a
lot shorter, along with quite a few other philosophers.

~~~
stareatgoats
Popper is immensely influential in science, well worth a closer study. Agree
there are some similarities with Socrates but as far as I know there was no
drive to have Popper drink poison (a tribute to the imprint of that ancient
Athenian on modern society maybe). Except perhaps in communist countries, the
expressed antithesis of Popper's "open society".

~~~
gboudrias
> Popper is immensely influential in science, well worth a closer study

Yep, pretty much invented the falsification principle. Imagine a time when
scientists often tried to prove things true. That was science before Popper.
This makes him the greatest contributor to science that I know of since
Francis Bacon.

~~~
foldr
>Imagine a time when scientists often tried to prove things true

The philosophers of science that Popper was criticizing didn't think that
scientists should try to prove that theories were true. They thought that
scientists should try to show that theories were likely to be true given the
available evidence. Popper was a radical skeptic regarding epistemic
probability, and thought that it was impossible to probabilistically confirm
scientific theories.

~~~
gboudrias
Well, yes, fair enough. But the main point is that scientific progress was
greatly accelerated thereafter. In that sense there is a before and after him,
and anyone who would choose to be anti-Popper (nowadays) is generally an
epistemic relativist who doesn't believe in the idea of progress, or sometimes
even the scientific enterprise, at all.

~~~
foldr
Most philosophers of science think that Popper was fundamentally wrong about
induction and demarcation, but few of them are epistemic relativists.

~~~
gboudrias
After some research, I understand that falsification is not seen as a
sufficient criteria for demarcation as Popper probably saw it. But do you not
agree that the idea of falsification as a bare minimum was revolutionary? That
was the main point of my original comment.

Apologies to anyone I might have offended by accidentally bundling them with
relativists.

------
wuzamarine
Popper is a paradox because his falsifiability violates the math Law of Non
Contradiction.
[https://en.wikipedia.org/wiki/Mathematics#Mathematics_as_sci...](https://en.wikipedia.org/wiki/Mathematics#Mathematics_as_science)
Philosophy has no place in Science. The Scientific Method is based on
'principles' and theorems/math based not philosophies. Karl is the real
inventor of modern pseudoscience (lipstick on a pig). The final cog in The
Scientific Method ->
[https://www.ncbi.nlm.nih.gov/books/NBK97153/#ch2.s3](https://www.ncbi.nlm.nih.gov/books/NBK97153/#ch2.s3)
^^hasn't changed since it sparked the entire Industrial Revolution and still
100% effective as is. ..
[https://en.wikipedia.org/wiki/Law_of_noncontradiction](https://en.wikipedia.org/wiki/Law_of_noncontradiction)

------
melling
Nassim Taleb, the author of Fooled by Randomness and the Black Swan, is a fan
of Popper.

~~~
mulligan
> Popper abhorred philosophers who argue that scientists adhere to theories
> for cultural and political rather than rational reasons.

~~~
coldtea
Well, he might abhorred them, but he was empirically wrong in tons of cases on
the matter.

------
bikenaga
The first chapter "Conjectural Knowledge" of his book "Objective Knowledge" is
a discussion of his proposed solution to the problem of induction.

His theories of science (and in particular, of falsification) are explained in
his book "Conjectures and Refutations". I read it years ago when I was in grad
school.

Popper's writing is clear and jargon-free, so anyone who is interested in his
ideas should take a look at some of the original sources.

Finally, "Wittgenstein's Poker" by David Edmonds and John Eidinow takes an
argument between Wittgenstein and Popper as a starting point for exploring
their lives and work.

------
chicob
This whole interview sounds a lot like someone finally getting the courage to
get even with an elderly man by exposing some petty aspects of his homely
habits while only superficially mentioning his work.

It seems the most detailed and thorough paragraph is the one devoted to the
spelling of 'Popperazzi'.

------
8bitsrule
Funny, funny stuff!

 _Popper glared at me. Then his expression softened, and he placed his hand on
mine. “I don 't want to hurt you,” he said gently, “but it is a silly
question."_

Very sly form of argument, that.

------
yters
I never understood how falsificationism is supposed to workaround the
shortcoming of inductivism.

Say I have coin that I predict will always flip heads. The first flip is
tails. Hypothesis falsified! But, that still tells me nothing about the future
if the coin is fair.

For falsification to work, we have to assume a priori there is not a uniform
distribution over events. In which case, we can do something like Solmonoff
induction anyways.

So, it looks like falsification is only useful if induction is also useful. In
which case, falsification is not a workaround for induction's problems.

~~~
lisper
Falsification is only a small part of the story. The other part, the much more
important part, is explanatory power. David Deutsch does an excellent job of
explaining this in his book The Fabric of Reality, mainly in chapter 7. Highly
recommended.

Induction, BTW, is completely invalid as a mode of reasoning (speaking here of
logical induction, not mathematical induction). You can flip a coin 10,000
times and have it come up heads every time and still not be able to validly
conclude that it will come up heads every time (there are a lot of ancillary
assumptions that go into the deductive inference, none of which are
justified). On the other hand, you can _examine_ the coin, see that there are
heads on both sides, and _immediately_ conclude (soundly) that it will come up
heads every time _because_ you can provide an _explanation_ : one of the two
sides must come up, and they are both heads!

~~~
yters
That's just pushing the problem up a level.

Adding an explanation is proposing a model for the coin's behavior. Regardless
of the model proposed, and whether it is confirmed or refuted, if the coin is
fair you learn nothing.

On the other hand, if the coin is not fair, Solomonoff induction works.

~~~
lisper
> if the coin is fair you learn nothing.

But that is simply because the theory that a coin is fair cannot be falsified
with one data point. (Well, that's actually not quite true. It can't be
falsified with a single data point which is "heads" or "tails". It could be
falsified if the coin lands and breaks into two pieces revealing some internal
mechanism that makes it unfair.)

> if the coin is not fair, Solomonoff induction works.

No, it doesn't. It is possible (given sufficient technology) to produce a coin
that generates a sequence of flips that is indistinguishable from fair for any
finite number N of flips, but which then produces HEADS forever after the Nth
flip. Moreover, it is possible to _know_ that this will happen _without even
flipping the coin_!

~~~
yters
The problem is how do you gain these explanations in the first place without
appealing to inductivism? The process of examining a thing to propose a theory
about its operation seems indistinguishable in my mind from the inductivist
approach of deriving general theories from particular observations. Both
approaches make the same assumption of a consistent underlying order behind
the observations we make.

~~~
lisper
This is the unsolved problem of "hypothesis formation." It's something that
brains do that we do not yet fully understand. It's an active area of
research. But the process of explanatory hypothesis formation is distinct from
induction. Induction says, e.g. "Every crow I have ever seen has been black,
therefore I conclude that all crows are black." (They aren't, BTW.
[http://www.birds.cornell.edu/crows/whitecrows.htm](http://www.birds.cornell.edu/crows/whitecrows.htm)
[https://www.quora.com/Are-all-crows-black](https://www.quora.com/Are-all-
crows-black))

~~~
yters
Yes, so it seems like falsificationism just pushes the fundamental problem
elsewhere and renames it.

The basic problem of distinguishing between patterns and luck undermines both
falsification and induction.

As far as I know, there is no resolution to the problem. We just irrationally
assume there is no problem out of habit, as Hume states in his original work.
A leap of faith, if you will.

~~~
lisper
No. Falsification is necessary but not sufficient. The best theory is one that
has _two_ properties: 1) it is consistent with all the observed data (i.e. has
not been falsified) _and_ 2) it is a "good explanation". Explaining what is
meant by "good explanation" is too long for an HN comment, but roughly
speaking it means that it is _concise_ and _brittle_ \-- any modification
would cause it to become inconsistent with the data.

(So for example, conspiracy theories fail as explanatory theories not because
they are inconsistent with the data -- they generally aren't -- but rather
because they are not concise and brittle.)

~~~
yters
That sounds like Solmonoff induction. But, there is still the same problem.
Why are concise explanations better? Solomnoff justified this assumption by
claiming we are generated by a computable prior. But, that again pushes the
question back to why we can assume this. Otherwise, no observation justifies a
computable prior over random luck.

~~~
lisper
> Why are concise explanations better?

Because they require less effort to work with. Note that concise is only
better all else being equal. Being consistent with the observed data is
necessary, but not sufficient. We can only ever have a finite amount of data,
and any finite dataset is consistent with an infinite number of theories.
Conciseness is just a heuristic we use to select among the infinite
possibilities. It just turns out that in the universe we live in, concise
theories consistent with the data have a lot of predictive power. No one know
why our universe is this way. That's just how it turns out to be.

~~~
yters
"It just turns out that in the universe we live in, concise theories
consistent with the data have a lot of predictive power. No one know why our
universe is this way. That's just how it turns out to be."

How is this not inductivism?

~~~
lisper
What do you think inductivism is?

~~~
yters
My understanding is inductivism is deriving general rules from specific
observations. The idea that short descriptions are better because "that is how
it works" seems to be this sort of thing. From our observation of specific
short descriptions working we've derived the general rule that short
descriptions work better.

~~~
lisper
> inductivism is deriving general rules from specific observations

OK, on that view, yes, they are the same. But inductivism is generally
understood to be more specific than that. It is generally understood to be a
_particular way_ of deriving general rules from specific observations, namely,
by simply generalizing the data into patterns without any regard for causal
mechanisms. So, for example, if you see (say) 100 crows and they are all
black, induction tells you to conclude that all crows are black without ever
asking _why_ crows are black.

~~~
yters
It's the same sort of problem of induction that Hume pointed out in his
original argument. Nothing substantially changes if we substitute "short
explanations are better" for "sun rises in the morning".

The basic problem remains, though we've consolidated many problems of
induction into one.

~~~
lisper
> Nothing substantially changes if we substitute "short explanations are
> better" for "sun rises in the morning".

No, that's not true. The operative word is "explanation", not "short".
Explanation changes everything. It is not enough to say, "The sun has risen
every day in the past, therefore it will continue to rise in the future." You
have to explain _why_ the sun has risen every day in the past (i.e. the earth
is round, it rotates about its axis, yada yada yada). Conciseness is not as
much a requirement as it is a consequence of the more primary requirement of
being a good explanation and consistent with all available data. In actual
practice, these requirements generally eliminate all theories but one. It just
turns out that those theories tend to be concise.

------
jimhefferon
> pseudo-scientific theories, like astrology and Freudian psychoanalysis

Kind of a bold take from SciAm.

~~~
TangoTrotFox
No, it's not. You're inappropriately cutting off the sentence: _" He is best-
known for the principle of falsification, a means of distinguishing pseudo-
scientific theories, like astrology and Freudian psychoanalysis, from genuine
ones, like quantum mechanics and general relativity."_

Falsification is critical to 'real' science, as otherwise the value of what is
said rests solely on how it is said rather than what is said. For instance I
could say that there's an invisible massless gremlin resting on your shoulder,
but you can't tell it's there as it only interacts with other invisible
massless gremlins and gravity. Obviously nobody would believe this, because it
sounds absurd. But that's not why you shouldn't believe it. The reason you
shouldn't believe it is believe it is because it's not falsifiable. You're
left trying to prove that there is no invisible massless gremlin on your
shoulder, which is something you cannot do.

Predictiveness is of course also critical, but predictions that cannot be
falsified are irrelevant. For instance 100 wrong astrology predictions in a
row does not falsify astrology. It just means 100 predictions ended up being
not true for some individual or another. But because we can happily ignore the
times when predictions of astrology are wrong means you ought also be happy to
ignore all of the times that it's right - as it's saying nothing where
accuracy matters.

------
blueprint
TIL proving something is not true is not proving the negative to be true. Not.

~~~
escherplex
For the fun of it, try an embedded factoid: 'blueprint' is happy to have
committed some atrocity X (without negating X)

~~~
blueprint
Huh? Do you know what happy means

~~~
escherplex
Nah, that's a corollary to Popper's observation of a problem with all
'definitions' in that terms are defined using terms which themselves remain
undefined which points to an implicit universal subjectivity, which
contemporary phenomenology inspired by Husserl attempts to skirt. The above
was a counterargument used on a HS hacker classmate's contention that any and
all questions could be formulated requiring only a yes/no true/false answer.
Prefixing a malicious factoid with a requisite subjective judgment and
requiring a categorical response illustrates an ill-formed [but possible]
question incapable of being affirmed or negated by any respondent.

~~~
blueprint
As long as happiness and subjectivity are not well defined by the asker,
answers to questions formulated using such definitions necessarily seem to
them to be ill-defined...

