The fact that there are myths about Zeus is evidence that Zeus exists.
That doesn’t look useful to me.
By the same token, my mentioning here the name of the monster Ygafalkufeoinencfhncfc is evidence that it exists. Funnily enough, the same reasoning provides evidence for the monster Grrapoeiruvnenrcancaef and a VERY large number of other, ahem, creatures.
No it doesn’t. Most of the creatures in that class have, in fact, not been mentioned by you or anyone else.
If one of dem monsters exists, that would be evidence that more of dem monsters exist.
Realize then that a conclusion of “one of those monsters exists” is just assigning a high probability. It follows that just increasing the probability of “one of those monsters exists” also increases the probability ýou’d assign to more monsters of its class existing. It’s a continuous updating relationship, there’s no discontinuous jump in the belief in other monsters of the class which only occurs once you’re sure that one of them exists.
Compare this to seeing an alien-engineered kaiju and then being less surprised at Godzilla (even if that’s only in a neighboring class).
I’d think that how much mentioning a monster updates the probability that it exists depends on the context of mentioning the monster. Furthermore, mentioning it in the context of examples of probability should score particularly low in this regard.
Do you mean that if I bothered to write a short story about how I met the monster Ygafalkufeoinencfhncfc while hiking in remote mountains and how all the locals were like “Oooh, there is something there but we don’t talk about it”—in such a case you’d update your probabilities higher?
P.S. Oh, an now we have TWICE the amount of evidence for Ygafalkufeoinencfhncfc compared to what we had a few minutes ago. Can we extrapolate the trend? :D
If you wrote a short story about a monster, there’s some chance that the monster exists, there are legends about it, one of those legends made its way to you, and you then chose to use it in your story. Thus, if I never heard of the monster, then you wrote such a story and I had no further information about your story-writing process, that would indeed increase my estimate that the monster exists by a miniscule amount.
If you wrote the story specifically to prove a point in a lesswrong discussion about monster names that are pulled out of thin air, that would be further information, so my estimate wouldn’t increase in the same way.
Moreover, it’s not twice the evidence anyway, since the story and the lesswrong post aren’t independent.
Oh, an now we have TWICE the amount of evidence for Ygafalkufeoinencfhncfc compared to what we had a few minutes ago. Can we extrapolate the trend?
Note: It’s not a linear trend. If you mention the name one million times, it does not make it one million times as likely. Also, being mentioned one million times by the same person is not the same evidence as being mentioned by one million people, once by each. And even that is not a linear trend.
We have some misunderstanding here. My best guess is that you think evidence makes something likely, while the typical usage here is that evidence makes things more likely. An example: Imagine that according to your best knowledge, some thing X has a probability 0.000001. Now you get some new information E, and based on all the knowledge you have now, the probability of X is 0.000001001.
On one hand, the information E increased the probability of X from 0.000001to 0.000001001. This is what we mean by saying that E is an evidence for X. It made it more likely.
On the other hand, even the increased probability is pretty close to zero. Therefore, more likely does not imply likely or even worth considering seriously (you can imagine even more zeroes before the first nonzero digit).
Similarly, probability of Ygafalkufeoinencfhncfc is pretty close to zero, but not exactly zero. Mentioning it on a discussion forum (choosing this specific topic instead of other millions of topic that could have been chosen) slightly increases the probability (at the cost of those other topics that were not chosen to be mentioned). The change is very small, but technically it is an increase. That’s why we call it evidence for Ygafalkufeoinencfhncfc.
Troy and Mycenae were not mythical cities—they were described in many writings other than the Iliad. There wasn’t much doubt that they existed.
Oh, and the myth about Schliemann is wrong—see Wikipedia:
Though it is widely believed that Heinrich Schliemann was responsible for starting archaeology on his own with the discovery of Troy, this is inaccurate. Schliemann became interested in digging at the mound of Hisarlık at the persuasion of Frank Calvert. The British diplomat, considered a pioneer for the contributions he made to the archaeology of Troy, spent more than 60 years in the Troad (modern day Biga peninsula, Turkey) conducting field work.
Troy and Mycenae were not mythical cities—they were described in many writings other than the Iliad. There wasn’t much doubt that they existed.
What? I don’t know of any writing that referred to Troy and Mycenae except the ones that directly related to the myths (I never said it was just Iliad of course, I mean the entire corpus of Greek myths).
We have a few Egyptian incriptions of the era that mention “Mukana” or some such, and perhaps a Hittite inscription that refers to some name similar sounding to Ilium, but those hardly count as “descriptions”—just a mention of a foreign city/country name without evidence to its location or anything really relating to it.
The evidence of the myths were pretty much the only evidence we had about Troy and Mycenae prior to the physical discovery of their remains.
What? I don’t know of any writing that referred to Troy and Mycenae except the ones that directly related to the myths (I never said it was just Iliad of course, I mean the entire corpus of Greek myths).
First, the question of whether the Trojan war was fiction is different from the question of whether the city of Troy was real and actually existed. It seems to me that during the first half of the XIX century there were claims that the Trojan war didn’t actually happen but was just imagined by Homer—but I don’t think that the mainstream consensus of that time insisted that the city of Troy was invented by him as well.
In fact, if you look at ancient texts you’ll find Troy being mentioned and discussed by such people as Herodotus and Thucydides. It’s not that their word should be taken as gospel, but their writings aren’t usually called “myths”.
All the texts described (Herodotus, Thucydides, etc) in your link only seem to discuss Troy in the context of the Trojan war which was itself known to the Greeks via the work of the myths passed down. So it seems strange to say that we knew Troy existed, but we doubted that the Trojan war was real.
Thucydides likewise mentions Mycenae—and he argued in favour of taking the poets’ words seriously about the past importance of Mycenae, though at his time no physical evidence of such remained (the location was by Thucydides’s time become mere insignificant villages).
which was itself known to the Greeks via the work of the myths passed down
Around the time of the Ancient Greeks and Romans, do you distinguish “myth” and “history” at all? It seems to me you’re calling everything without physical evidence a “myth”.
That doesn’t look useful to me.
By the same token, my mentioning here the name of the monster Ygafalkufeoinencfhncfc is evidence that it exists. Funnily enough, the same reasoning provides evidence for the monster Grrapoeiruvnenrcancaef and a VERY large number of other, ahem, creatures.
True.
No it doesn’t. Most of the creatures in that class have, in fact, not been mentioned by you or anyone else.
Also true.
If one of dem monsters exists, that would be evidence that more of dem monsters exist.
Realize then that a conclusion of “one of those monsters exists” is just assigning a high probability. It follows that just increasing the probability of “one of those monsters exists” also increases the probability ýou’d assign to more monsters of its class existing. It’s a continuous updating relationship, there’s no discontinuous jump in the belief in other monsters of the class which only occurs once you’re sure that one of them exists.
Compare this to seeing an alien-engineered kaiju and then being less surprised at Godzilla (even if that’s only in a neighboring class).
True. But then I can write a one-line Perl script which will bring into being evidence for a LOT of monsters.
Which itself brings into being the question of what kind of evidence the output of a RNG is. Or, perhaps, what kind of evidence does software produce.
I’d think that how much mentioning a monster updates the probability that it exists depends on the context of mentioning the monster. Furthermore, mentioning it in the context of examples of probability should score particularly low in this regard.
Do you mean that if I bothered to write a short story about how I met the monster Ygafalkufeoinencfhncfc while hiking in remote mountains and how all the locals were like “Oooh, there is something there but we don’t talk about it”—in such a case you’d update your probabilities higher?
P.S. Oh, an now we have TWICE the amount of evidence for Ygafalkufeoinencfhncfc compared to what we had a few minutes ago. Can we extrapolate the trend? :D
If you wrote a short story about a monster, there’s some chance that the monster exists, there are legends about it, one of those legends made its way to you, and you then chose to use it in your story. Thus, if I never heard of the monster, then you wrote such a story and I had no further information about your story-writing process, that would indeed increase my estimate that the monster exists by a miniscule amount.
If you wrote the story specifically to prove a point in a lesswrong discussion about monster names that are pulled out of thin air, that would be further information, so my estimate wouldn’t increase in the same way.
Moreover, it’s not twice the evidence anyway, since the story and the lesswrong post aren’t independent.
Note: It’s not a linear trend. If you mention the name one million times, it does not make it one million times as likely. Also, being mentioned one million times by the same person is not the same evidence as being mentioned by one million people, once by each. And even that is not a linear trend.
Nobody said it was. In any case, I was talking about the amount of evidence, not about what does that imply in terms of belief probabilities.
A “linear trend” in probabilities would have big issues, of course, because there are hard caps at zero and one.
We have some misunderstanding here. My best guess is that you think evidence makes something likely, while the typical usage here is that evidence makes things more likely. An example: Imagine that according to your best knowledge, some thing X has a probability 0.000001. Now you get some new information E, and based on all the knowledge you have now, the probability of X is 0.000001001.
On one hand, the information E increased the probability of X from 0.000001to 0.000001001. This is what we mean by saying that E is an evidence for X. It made it more likely.
On the other hand, even the increased probability is pretty close to zero. Therefore, more likely does not imply likely or even worth considering seriously (you can imagine even more zeroes before the first nonzero digit).
Similarly, probability of Ygafalkufeoinencfhncfc is pretty close to zero, but not exactly zero. Mentioning it on a discussion forum (choosing this specific topic instead of other millions of topic that could have been chosen) slightly increases the probability (at the cost of those other topics that were not chosen to be mentioned). The change is very small, but technically it is an increase. That’s why we call it evidence for Ygafalkufeoinencfhncfc.
I understand the argument. I don’t accept it.
No. We can’t extrapolate a trend. That’s what”You cannot expect that future evidence will sway you in a particular direction” means.
That there were myths about Troy and Mycenae was highly useful to Heinrich Schliemann who discovered them and proved their existence.
Troy and Mycenae were not mythical cities—they were described in many writings other than the Iliad. There wasn’t much doubt that they existed.
Oh, and the myth about Schliemann is wrong—see Wikipedia:
What? I don’t know of any writing that referred to Troy and Mycenae except the ones that directly related to the myths (I never said it was just Iliad of course, I mean the entire corpus of Greek myths).
We have a few Egyptian incriptions of the era that mention “Mukana” or some such, and perhaps a Hittite inscription that refers to some name similar sounding to Ilium, but those hardly count as “descriptions”—just a mention of a foreign city/country name without evidence to its location or anything really relating to it.
The evidence of the myths were pretty much the only evidence we had about Troy and Mycenae prior to the physical discovery of their remains.
First, the question of whether the Trojan war was fiction is different from the question of whether the city of Troy was real and actually existed. It seems to me that during the first half of the XIX century there were claims that the Trojan war didn’t actually happen but was just imagined by Homer—but I don’t think that the mainstream consensus of that time insisted that the city of Troy was invented by him as well.
In fact, if you look at ancient texts you’ll find Troy being mentioned and discussed by such people as Herodotus and Thucydides. It’s not that their word should be taken as gospel, but their writings aren’t usually called “myths”.
See e.g. http://riversfromeden.wordpress.com/2011/09/06/the-trojan-war-in-greek-historical-sources/ for more details.
All the texts described (Herodotus, Thucydides, etc) in your link only seem to discuss Troy in the context of the Trojan war which was itself known to the Greeks via the work of the myths passed down. So it seems strange to say that we knew Troy existed, but we doubted that the Trojan war was real.
Thucydides likewise mentions Mycenae—and he argued in favour of taking the poets’ words seriously about the past importance of Mycenae, though at his time no physical evidence of such remained (the location was by Thucydides’s time become mere insignificant villages).
Around the time of the Ancient Greeks and Romans, do you distinguish “myth” and “history” at all? It seems to me you’re calling everything without physical evidence a “myth”.