[SEQ RERUN] What is Evidence?

post by MinibearRex · 2011-09-05T05:57:27.291Z · LW · GW · Legacy · 9 comments

Today's post, What is Evidence? was originally published on 22 September 2007. A summary (taken from the LW wiki):


Evidence is an event connected by a chain of causes and effects to whatever it is you want to learn about. It also has to be an event that is more likely if reality is one way, than if reality is another. If a belief is not formed this way, it cannot be trusted.

Discuss the post here (rather than in the comments to the original post).

This post is part of the Rerunning the Sequences series, where we'll be going through Eliezer Yudkowsky's old posts in order so that people who are interested can (re-)read and discuss them. The previous post was Burdensome Details, and you can use the sequence_reruns tag or rss feed to follow the rest of the series.

Sequence reruns are a community-driven effort. You can participate by re-reading the sequence post, discussing it here, posting the next day's sequence reruns post, or summarizing forthcoming articles on the wiki. Go here for more details, or to have meta discussions about the Rerunning the Sequences series.


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comment by Navanen · 2012-12-18T04:16:13.091Z · LW(p) · GW(p)

Is there any decent literature on the extent to which the fact of knowing that my shoelaces are untied is a real property of the universe? Clearly it has measurable consequences - it will result in a predictable action taking place with a high probability. Saying 'I predict that when someone will tie his shoelaces when he sees they're undone' is based not on the shoelaces being untied, nor on the photons bouncing, but on this abstract concept of them knowing. Is there a mathematical basis for stating that the universe has measurably changed in a nonrandom way once those photons' effects are analysed? I'd love to read more on this.

This was a comment from the original post, and I agree with this sentiment. There was no response, so I'm wondering if anyone can answer this question now.

Note: I don't know who the author is because I have Kibitzing on in Chrome and for some reason I cannot turn it off right now.

comment by Armok_GoB · 2011-09-05T20:47:50.515Z · LW(p) · GW(p)

Sort of tangential, hut here is a list of reasons why my beliefs are not as contagious as they could be:

I am unable to provide evidence that distinguishes me from a reference class that's much less rational than me on average. Lack of introspective access or inability to serialize. Bandwidth issues, the belief is simply to large with to many details. Basilisk infestation.

This leads to me sometimes needing to say somehting like roughly "I believe statement X with 90% certainty, this fact combined with my argument for it should raise you from a 5% certainty to a 20% certainty." which is kind of hard and tend to my frustration to be treated like "I believe X with 20% certainty", to the point where I've stopped even trying.

Replies from: None
comment by [deleted] · 2011-09-06T02:49:07.148Z · LW(p) · GW(p)

I am unable to provide evidence that distinguishes me from a reference class that's much less rational than me on average...Bandwidth issues, the belief is simply to large with to many details.

Strongly agree with both of these. I have a lot of trouble talking to people (even some of my closest friends!) about topics like cryonics, death, or even plain old rationality because of bandwidth and weird-sounding support. Does anyone know how to combat these effects besides simply (a) telling people to be patient, and (b) explaining why the absurdity heuristic is bad (which itself is a long discussion)?

Replies from: XiXiDu, lessdazed
comment by XiXiDu · 2011-09-06T10:44:20.073Z · LW(p) · GW(p)

Ask them questions, about their preferences and how they are going to realize them, until any internal incoherence is revealed. For example (roughly), ask them if they care about their health and if they want to see the future. At some point they will have to draw a line between what they are already doing to survive and cryonics. Ask why they draw that line...

Questioning is sometimes better than preaching because it causes the people who are questioned to reveal their own ignorance or incoherence while it allows those who ask the questions to act submissively.

Replies from: None
comment by [deleted] · 2011-09-06T11:30:38.225Z · LW(p) · GW(p)

Thank you! I'll definitely give that technique a try.

comment by lessdazed · 2011-09-06T12:10:09.381Z · LW(p) · GW(p)

If it were easy, this website wouldn't exist.

I have a lot of trouble talking to people (even some of my closest friends!) about

That phrase is used when there are only problems of understanding, it's also used when there is only emotional stress in the speaker. The context above makes me think you at least meant the former, did you choose that phrase because you also meant the latter?

Replies from: None
comment by [deleted] · 2011-09-06T19:44:18.284Z · LW(p) · GW(p)

No, it was poor wording on my part. I 95% mean the former as implied by the conext, 5% the latter because I do have emotional difficulty with the fact that I can't explain something as simple as "death is bad."

Replies from: lessdazed
comment by lessdazed · 2011-09-06T20:11:44.719Z · LW(p) · GW(p)

Have you tried starting with: "Maybe death is bad, maybe death is good, maybe death is neither."

For audiences that do not understand that net good outcomes come from events with negative outcomes, append "depending on the circumstances."

Replies from: None
comment by [deleted] · 2011-09-06T21:02:00.927Z · LW(p) · GW(p)

Interesting, that approach hadn't occurred to me--I've mostly been trying variants of Fable of the Dragon-Tyrant. I'll give that a try, thanks!