If you mean things like the base rate fallacy, then yes it does.
In the paragraph after the one you quoted, I gave an example of what I was discussing.
If you mean that putting in random numbers for your priors doesn't solve your problems, then there isn't any method of considering evidence that fixes that in principle.
You can check the source of the evidence and try to make sure that you're not putting in random numbers but reliable data.
When considering hypotheses in the real world -- like "Does God exist?" or "Is my wife cheating on me?"-- Bayes' theorem doesn't encapsulate all the skills you need to arrive at a trustworthy answer. You must clearly understand what it is you're trying to establish -- Aquinas's conception of God is very different from your average Christian's. You must be willing to question beliefs that you are attached to or identify with -- maybe your wife is sleeping with anything that moves, or maybe you're a needlessly jealous, insecure husband. You must gather as much evidence as possible, including the evidence that you might initially deem to be irrelevant. You must be diligent, fastidious, and detached when performing the investigation -- not hiding behind "Oh, my wife would never do that" or allowing your emotions to effect your judgment.
People will have done all the above and still arrived at erroneous conclusions. Such is the difficulty of testing a hypothesis.
It is, actually. It's the Bayesian definition that evidence for X is something more likely to be true in a universe where X than in a universe where -X.
What you're saying here is that you use Bayes' theorem to inform your definition of "evidence".
If I used a different definition of evidence, that doesn't mean I'm saying something about Bayes' theorem. That simply means I use the word differently.
When it comes to evidence, I don't believe Bayes' theorem deals with the real-world problems that arise when considering a hypothesis. For example, it doesn't deal with the "garbage in, garbage out" problem.
As I said, we might plug the number of calls Uri Geller got into Bayes' theorem and because of the answer believe that supernatural events did actually occur. But that would be an incorrect conclusion because we have based our conclusion on the faulty premise that more calls means supernatural events are more likely to have occurred.
This is really a dispute over maths. The laws of probability are the law, they don't depend on word usage.
Explaining the way one uses a word isn't a statement about maths or the laws of probability either.
I'm not clear how this is relevant to the base rate fallacy though.
It's not. I was riffing on what you said.
Strictly speaking what's going on there is that you are collecting facts which might later turn out to be evidence for a hypothesis you have not articulated yet.
I was discussing ascertaining the trustworthiness of evidence concerning a hypothesis you are currently considering. Like an investigation into whether Uri Gellers phone calls were genuine reports of supernatural events, for example.
It doesn't change the definition of evidence though,
Of course not. I'm not trying to suggest that my usage of "evidence" is somehow better or superior than yours. I do think mine is more common, but that's a matter of opinion.
Perhaps a less abstract example would help
I don't think a less abstract example will solve a dispute over word usage.
What would have been evidence for Uri Geller having psychic powers is if he got more calls than normal people when he did that stunt.
And even if they did receive a statistically significant number of calls, perhaps people lied, grouped together and phoned in supernatural events that hadn't actually occurred.
If all you have is the one anecdote then it does count as evidence, but only in a strictly philosophical or mathematical sense. Not in any practical sense though since the shift in the relevant p value isn't going to be visible in the first twenty or thirty decimal places and I doubt anyone alive has that level of precision in their decision-making.
I don't have a problem with dismissing evidence if it truly is highly irrelevant. I think the problem is that in some cases evidence that at first seems irrelevant turns out to be important.
How relevant a piece of evidence truly is might not become apparent even after significant consideration. This is why, for important matters, I explore as much evidence as possible, even the seemingly irrelevant evidence.
I think I might have to write something specifically addressing this misconception because a few people seem to have picked it up.
I think our disagreement is to do with our differing usage of "evidence", not a misconception. I'd say that a sole anecdote of someone seeing Russell's teapot can be considered evidence for its existence, even though it's not credible evidence.
It's only evidence for the existence of Russell's teapot if more people say they have seen it than you would expect in a universe where Russell's teapot does not exist.
I would add that different situations require different standards of evidence, depending on how willing we are to accept false positives. The fire service only requires one phone call before they respond.
How do people use the karma system here? If you agree vote up, if you disagree vote down? That will create a very insular community.
My five cents.
Direct counterargument: I would phrase my attitude to ethics as: "I have decided that I want X to happen as much as possible, and Y to happen as little as possible." I'm not "believing" anything - just stating goals. So there's no faith required.
I'd agree. By switching from morals to your individual preferences, you avoid the need to identify what is objectively good and evil.
I agree that religion isn't the source of morality. In my experience, atheists believe in good and evil just as much as religious people do.
To believe you can somehow make the world objectively better, even in a small way, you must still believe in some sort of objective good or evil. My position is the sacrilegious idea that there is no objective good or evil -- that the universe is stuff bouncing and jumping around in accordance with the laws of nature. Crazy, I know.
There is a difference between the universe itself and our interpretations of the universe. A moral is a judgement about the universe mistaken for an inherent property of the universe.
In order to establish that something is better than or superior to something else, we must have some criteria to compare them by. The problem with objective good and evil, if you believe they exist, is that there is no way to establish the correct criteria.
A lion's inclination to kill antelope isn't inherently wrong. The inclination is simply the lion's individual nature. Because you care about the antelope's suffering doesn't mean the lion should. The lion isn't wrong if it doesn't care.
We are all individuals with different wants and desires. To believe there is a one-size-fits-all moral code that all living creatures should follow is lunacy.
A point everyone seems to be missing here is that there ARE no scientific facts.
There are scientific facts, as the phrase is commonly understood. Anything that is independently verifiable is considered to be a scientific fact. Facts are not built upon theories; theories are built upon facts.
You would be right to say that that sensible scientists don't claim that they are definitely correct. They tentatively believe what the available evidence currently suggests. No more, no less.
If someone believes the Bible is central to question of whether God exists, you can challenge that without having a definition of "evidence" that is informed by Bayes' theorem.
It could be flawed if there are things that effect the number of phone calls other than Geller's proposed psychic powers. One show might get more calls but also have more viewers, and that obviously doesn't make Geller more likely to be psychic during that particular show.
But I am in agreement with you generally with the Uri Geller example. I don't think phone calls to a television show would alone change my mind, but if we did live in a world where he truly did have psychic powers, I would hope that such evidence would lead me to investigate the matter further.