8, especially, is an especially eloquent formulation of Aumann's Agreement Theorem.
It may or may not be eloquent, but it sure as hell is not a formulation of Aumann's Agreement Theorem.
Do not fear to be eccentric in opinion, for every opinion now accepted was once eccentric.
There's some confirmation bias here.
Sounds like survivorship bias to me: yes, every opinion now accepted was once eccentric, but most eccentric opinions of the past have been rejected so thoroughly that we're unlikely to have ever heard of them.
However, if we accept the premise of the quote that every opinion now accepted was once eccentric (and the implicit inference that every opinion that will be accepted in the long run is now eccentric), and your goal is to have opinions that are accepted in the long run, then it is true that you have to pick opinions that are currently eccentric (even if it is also true that most eccentric opinions, both in present and past, are crazy ones that never become accepted).
The main problem is that the premise is false. Most conventional opinions of the past are still accepted today (e.g. "clouds lead to rain", "fire is hot", et cetera).
(e.g. "clouds lead to rain", "fire is hot", et cetera).
I suspect the kind of opinion the quote is talking about is as defined here; a belief or judgment that rests on grounds insufficient to produce complete certainty. Neither “Fire is hot” nor “Clouds lead to rain” count as examples of this as most people have a fair amount of evidence on hand to back those beliefs up.
In light of this, could you please provide alternative examples of conventional opinions that were also held in the past?
I suspect the kind of opinion the quote is talking about is as defined here; a belief or judgment that rests on grounds insufficient to produce complete certainty.
Adherents of rule #1, however, will never have grounds sufficient to produce complete certainty, in which case, "fire is hot" is an opinion by that definition.
However, a a pure counterexample rather than a mere logical knot:
could you please provide alternative examples of conventional opinions that were also held in the past?
Sure. "Murdering your brother out of jealousy is wrong." That's a fairly conventional opinion, no?
If you define "opinion" as something which is not obviously true then every opinon had once to be at least a bit eccentric by definition.
every opinon had once to be at least a bit eccentric by definition.
I'm having trouble parsing that, could you re-phrase?
Also it's not so much about what I'm defining "opinion" to be, but rather about what the quote means when it says "opinion". If we're going to say that the quote is wrong, we should at least aim to attack what the quote is intended to mean, rather than what we can interpret it to mean.
Varying forms of xenophobia have existed throughout the ages and those ideas are still alive and kicking today.
However within a good deal western media (at least in England) xenophobic ideals are portrayed as to the "far right", and essentially eccentric. Whereas back in the day racism/nationalism was normal, and to not conform to that was considered eccentric.
Also I was looking for something a little less general than just xenophobia, a lot of opinions fall under that category.
To adapt a quote of Douglas Adams:
There is a theory which states that if ever anyone discovers a flaw in the Set-Theoretic Universe, it will instantly disappear and be replaced by something with an even more bizarre and complex specification. There is another theory which states that this has already happened.
With that in mind, it's interesting to look at Russell's list of 10 commandments. A conspicuous and unusual characteristic of their design is that each of them (apart from 1.) has two halves: a principle, and then a justification. Not exactly the conventional style when issuing commandments.
It conjures an image of a first draft, perhaps more simplistic, more conventional in style - in which the eagle eye of Russell, always ready to give careful consideration to any self-referential aspects of the system, discovers - a Paradox!
:D
This doesn't seem to be specific to teachers at all. How about these instead (off the top of my head)?
Betrand Russell's Ten Commandments for teachers.
I find this to be of use not just for teachers but for rationalists in general. #8, especially, is an especially eloquent formulation of Aumann's Agreement Theorem.