## When should we doubt our knowledge?

Discussions on the nature of reality and knowledge. What is reality? How do we know it?

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### When should we doubt our knowledge?

Generally epistemology seeks to address how we know. But I am curious as to what people think about when we should doubt our knowledge. This obviously assumes we have knowledge in the first place.

Note, I am not asking when we CAN doubt our knowledge. We can do that pretty much all the time. See Descartes, among others. No, I am asking when we should. And I am not asking when we should give up our previous knowledge as being wrong. Doubt of knowledge is the issue I am interested in, not rejection of knowledge.

Some might say we should always doubt our knowledge. I don't. As I type this, I have no doubt that I am typing it on a computer while sitting in a chair. I know that is the case, I have no doubts that is the case.

But if I were to wake up suddenly in bed at home at 3 in the morning, I should doubt it was the case that I was typing this on a computer. Maybe I was, maybe I was dreaming about something I actually did. But maybe I was dreaming about something I did not do. A sudden and large scale perceptual change like that of going from dreaming to awake seems good reason to doubt the "dream" events as being real.

I would be interested to hear anyone's take on doubting knowledge. Either examples of times you have doubted what you thought you previously knew, or general principles on when we should go from "know" to "might not know".

Ursa Minimus
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### Re: When should we doubt our knowledge?

I was once sleeping at a friends home, in the basement. At some point I awoke and found I was in absolute complete blackness. I stood up, and could feel the floor, but that is all I knew about my surroundings. I did not dare take a step because I had not idea where it would take me. Talk about doubting your knowledge? I had no knowledge at this point. As I recall lack of knowledge is anxiety and fear. I don't know if this is off yopur topic.

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### Re: When should we doubt our knowledge?

My first impression is that the case for doubting occurs on the occasion of someone asking "Are you sure?" (Much more could be added here.) However, in as much as you've regarded it as knowledge rather than belief, one in which my retort might call for any response to it to say that there is no doubt, it would mean that doubting knowledge is impossible or that indubitable knowledge is a redundancy.

Despite this, of course, there is the matter of knowledge being associated with those who know, a property of individuals, as opposed to having some existence independent of them. And if humans are limited, and are unable to achieve indubitable knowledge, then there's something to be gained by adopting some sort of provisional form of knowledge, that has within it at least a psychological sense of certainty, yet remains doubtable on the basis that that it's based on a limited psychology. It is my understanding then that it is appropriate to adopt the word knowledge to much of the findings of science (thereby allowing a cumulation of scientific knowledge) on the basis that it has long been successful in its predictive capacities without exception.

The logic of this prevents it from being considered knowledge in its purest form, but instrumentally, it has proved to be of great value. Moreover, because such 'knowledge' is varyingly understood among scientists as solid, there will be some who invest their energies into considering alternative ideas that may better explain the observations, especially those having a larger scope. And should any of these bear fruit, old knowledge may evolve into new knowledge, allowing that old knowledge must still have its use within a limited range.

James
owleye
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### Re: When should we doubt our knowledge?

It depends very much on whether our knowledge is based on observation, inference, or revealed truth. Observation always includes an element of doubt since we never have the means to know the actual nature, characteristic, or value of that which we have observed. Even should our observation be perfect, we cannot know that, and must have some doubt.

An inference, since it depends on assumptions, also always has doubt. I may have only one cup and one ball, but I still must doubt whether the ball is under that cup. The doubt of an inference is harder to state since so much depends on the nature of the thing inferred, the intellectual honesty of those involved, and a clear definition of the inference.

Revealed truths have no doubt unless the recipient is unsure about the source.

Since I am an engineer, I doubt all knowledge, all the time. It's in the specs.

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### Re: When should we doubt our knowledge?

The answer relies on the approximate nature of knowledge. Absolutes as well as other conceptualization symbolically represent reality but only approximately. As all knowledge is acquired by the senses the senses would have to be capable of perfectly observing the object in all it's detail for knowledge of the object to be absolute. While technology can extend the abilities of the senses and transfer information to the brain otherwise unavailable to the senses this is never a perfect process.

I agree with Canadys a good enough approach is not only realistic but desirable as a practical matter.

That does not mean that exploring the inter workings of the mind, ignoring the false duality of mind and body, does not have value. Epistemology, logic, philosophy, are all ways to tweak the software of the brain improving the efficiency of translating sensory information. Focusing these studies on the nature of language appeals to me as the most effective course.

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### Re: When should we doubt our knowledge?

Nothing in science is based on actually fact just assumptions. You can go round and round driving yourself crazy thinking about it but at the end of the day you have to have faith in certain beliefs.

If we can measure something with our senses we should not doubt this measurement to be completely false but should be aware that it could be much less accurate than what we perceive. If we are here and part of "something" then we are in one way or another connected to it physically or mentally and can derive certain pattern by observation.

Any information we possess does not need to be correct but needs to convince us it eludes to being correct by our perceptions.

I hate to quote other but I think this sums it up best : "Justified true belief"

If nothing matters nothing matters. No harm in assuming it does matter and paying attention to it if this is the case. Everything is based on belief in our environments.

WHEN should we doubt? Always. Its to the degree we doubt that is the issue and that down to personal judgement. The most doubtless tool we have is mathematics and I for one doubt maths least of all BUT I still doubt its capabilities to tell me everything I want to know and I believe 1+1=2 but only 99.99R% and that is a good enough belief for me to cling to for my personal sense of reality.

Sorry if what I say isn't as clear to you as it is for me but I do my best ...

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### Re: When should we doubt our knowledge?

The situation you mentioned provides a clue to the answers you are seeking. That clue is the presence of a condition comprising elements that would not match according to your intuition. It would be indeed more difficult when in your dream you have finished typing and went to sleep, waking up at the usual time, this time for real, but only to find latter that you have not typed any into your computer. If the dream was so real, if it went so like natural, it will take some time to notice if the evidence is not immediately obvious. But that is an extreme. In common situations, there will be at least one discrepancy, something in the course of normal feelings and thinking – your intuition will notice it first.

Breaking these elements into smaller chunks would give us sub-elements that are not really new and suggest cybernetic relationships between knowledge and its constraints:

1. Goal
2. Evidence of arriving at/achieving the goal
3. Fixed constraints
4. Resources

1. Goal
You as a human being, aside from your conscious goals, have unconscious goals. Your brain is a goal-seeking devise – it is innate. These goals, conscious or/and unconscious, influence your thrust or doubt on knowledge. Any knowledge not supporting the goal may be abandoned or used as a guide but not as a rule. Not all goals are something novel, but they can also be states of (the same) equilibrium, though this equilibrium can vary within a certain range. Your perception of self is a kind of equilibrium, you will be thrusting or doubting some knowledge based on this equilibrium.

2. Evidence of arriving at the goal
Your own self, at least a part of it, as an automatic “servomechanism”, will not stop until you reach the evidence that its goal(s) have been achieved or maintained. (Some conscious goals however degrade). There will be then mechanisms that will maintain the evidence (s) and this will involved also an ongoing assessment of knowledge because the conscious and unconscious parts of our self are really “two sides of the same coin” – patterns that mutually influence each other at least by constraints.

3. Fixed constraints
There are parts within our self and the environment that are not within our control. They are something we need to adjust to and any relevant knowledge will be assessed accordingly.

4. Resources
There are parts within our self and the environment that we have control. These are some things or process we can use (and manipulate consciously) to achieve goals.

We are continually assessing our results and vary our actions to achieve goals and this will affect our thrust and doubt on related knowledge because consecutive attempts without success will make us learn to change our actions with a corresponding in our position towards the relevant knowledge.

In all of these processes, the brain maintains an on-going model of reality that is continuously and unconsciously checked with the world out there. This internal world is maintained or changed depending on conditions outside (that is, it is always updated by the brain whenever appropriate information is available to it).

So when should we doubt knowledge? It will depend on these elements at least. What is your goal? Will the knowledge be useful to achieve it? Will the knowledge limit or prevent you? Will it guide you? What are the things and processes in yourself and your environment you have control on? You do not have control on? How will you know you are progressing towards the goal and how will you adjust and change? What actions you have not taken yet and what (knowledge) prevents you? We then have the idea that thrusting or doubting knowledge depends upon these conditions of an individual or group. It will help to bring a particular knowledge to your focused attention and analyze constraints.

The last thing to consider (but not the least) is that systems are embedded in larger systems. Your goals as an individual exist in the goals of larger body beyond yourself. This relationship too will affect your stand towards knowledge. What knowledge supports the mutual co-existence of your goals and the goals of the larger whole?

In the end, for practical purposes, we will consider and weigh both usefulness and truth.
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### Re: When should we doubt our knowledge?

Hi Everyone,

When should we doubt our knowledge? "ALWAYS"!!!! (I'm also an Engineer..lol.)

Not sure of where this Quote came from but I like it: "Progress is hindered less by ignorance than by the conviction of ones knowledge."

For example, if I ask how much energy would be required to produce 1 ounce of gold from pure energy, then someone would do the math E=M(CC) or tremendous Energy in a small amount of Mass. But the math also translates to M=E/(CC) which would seem to say that Mass has very little energy. Anyway, joking aside.. :P

I'm fairly sure a Physicist would say something like "It would take all the energy ever produce by mankind to produce a tiny fraction of gold mass. Yet.. if the Universe started from Nothing and is now loaded with a tremendous amount of Mass and Energy, then the Universe has a few tricks up it's sleeves that we don't understand yet.

If we knew those tricks then it seems reasonable that someday we could exploit Vacuum Energy to configure Quantum Foam into Matter Symmetries such as Gold or Diamond. Imagine a portable machine that uses a 9V battery for Primer Energy. You select a material, punch a button and out pops any quantity of any basic matter, from Hydrogen to Uranium (Waits for laughter to quell). The deluxe model can produce food products via complex woven molecules (Still more laughter).

Ok, you don't have to tell me how many Laws this breaks. I'm not stupid (usually). But for those that laughed at the concept, review my Quote from above.

I say if the Universe can do it.. then I vote we should be able to do it too! All in favor say "Aye".

Best wishes,
Dave :^)

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### Re: When should we doubt our knowledge?

In our moralistic world would should certainly doubt anything we assume to be correct.
I personally get really worried when things start to make sense to me!

Saying that though ignorance is a gift not to be dwelt in IMO.

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### Re: When should we doubt our knowledge?

I rekon when emotions get involved then you should think twice.

but people kinda blow the whole epistemology thing out proportion..
Whut
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### Re: When should we doubt our knowledge?

A quick reply on one point for now:

CanadysPeak wrote:Since I am an engineer, I doubt all knowledge, all the time. It's in the specs.

Dave_Oblad wrote:When should we doubt our knowledge? "ALWAYS"!!!! (I'm also an Engineer..lol.)

Engineers doubt some things they "know" to be true. "The numbers say X is strong enough, but we'll go with X+20% to be safe". I get that. However, engineers don't doubt everything.

When should you doubt copper conducts electricity?

When should you doubt this bit of copper (points to a small wire in a circuit) conducts electricity?

In the first case, probably never. If you have some "copper" and find it doesn't conduct electricity, you will probably doubt it is copper, or doubt that it is a continuous run of copper, and never doubt the conductivity of copper.

In the second case, when the circuit does not function. And you should doubt every bit of the circuit in that case.

Should I doubt I am in a different chair now, typing on a different computer? No, there is no reason to doubt that. Should I doubt that 2 apples + 2 apples = 4 apples? Nope. If I see someone put 4 apples in a box and then dump them out and there are only 3 apples, I will doubt that they put them all in the box (slight of hand) or that one got stuck in the box. I will not wonder if 2+2=3.

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### Re: When should we doubt our knowledge?

Whut wrote:I rekon when emotions get involved then you should think twice.

but people kinda blow the whole epistemology thing out proportion..

/checks the forum

Seems like the place to blow it out of proportion! :P

That is a good practical piece of advice, to say check yourself when emotions are involved. I would also say that we should think twice about the cause of the emotions themselves. Sometimes when we blame others for our emotional reactions they are not the cause of them, or not the complete cause. Sometimes it is more about us than them, but it is much easier to blame them. Or credit them, in some cases, than to look at ourselves.

Ursa Minimus
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### Re: When should we doubt our knowledge?

Should I doubt that 2 apples + 2 apples = 4 apples

The problem with this analogy is that there are no 2 apples that are exactly the same. Each group of 4 apples will have variations. Numbers are abstractions that allow us to simplify reality and there in lies the problem. We can reasonably say that the concept or mental image of a horse is more perfect than the horse itself. The only meaning however in these kinds of statements is that symbology has an inherent exactness that may appeal to logic. Logic however is a poor substitute for experience. That is the beauty of science in so far as observations trump reason. There are facts that we don't deny but it is the complexity of the relative nature of those facts that make us question our understanding.

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### Re: When should we doubt our knowledge?

wolfhnd wrote:The problem with this analogy is that there are no 2 apples that are exactly the same. Each group of 4 apples will have variations.

Yet I still have no doubt about how many apples I have.

So, do you get confused when shopping for apples that are 2 apples for a dollar? Do you wonder what they mean by "2 apples"? Do you wonder which particular dollar you have that they will accept, given that all dollars must be different? Are you unsure of whether or not you have 2 apples in a bag? Might it be or 1 or 3?

x

xx

xxx

I know when I have 2 apples, and the clerk ringing me up knows too. I know how to select a dollar's worth of apples, and the clerk will agree.

Now, being unsure of the number of apples with pieces of apples, or apple sauce, that seems sensible. But whole apples? Seems to be going a bit too far to me.

Ursa Minimus
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### Re: When should we doubt our knowledge?

Apples may be sold by weight and then the variation becomes relevant. You also may select the apples based on inperfections or size if sold individually. The only point I'm trying to make is that simplification of calculations while necessary to function do not replicate actual conditions.

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### Re: When should we doubt our knowledge?

UM,

My perspective, and it is how I qualified my answer, is that counting apples is not simple to me when I am wearing my engineer hat. For example, I may well have to "count" several hundred thousands items (I've done this). Unless I am willing to sit and go "two hundred thousand, six hundred, forty-nine, two hundred thousand, six . . .", I must define what I mean by counting. That definition necessarily introduces some doubt - not the actual process, not the nature of the items counted, but the definition of counting. That doubt exists in all engineering activity, even when thinking about the resistance of copper (if you don't define that resistance adequately, two persons will get two valid answers, and that must introduce doubt). Doubt is (almost) different from safety margin. When I use a safety factor of 3 for a steel, only about 1.1 of that has to do with doubt; the rest has to do with other factors - factors perhaps not known, but still not doubt. For example, I once designed a mechanism that was required to function for thirty years in an alkaline desert with no inspection or mantenance. I used two times the thickness of steel otherwise indicated because: (1) corrosion testing indicated that the steel would lose about half it's strength; (2) double thickness was readily available; and, (3) a risk analysis showed that it would cost much more to design for thirty-five years than to simply pay the odd warranty claim at twenty-eight years (besides, twenty-eight years was beyond the financial "event horizon").

I see doubt as quantifiable, always present, and not in any sense bad. There's a fair amount more that i could use for illustration, but it would likely get pretty technical and boring as can be. The bottom line for most of us is that, when we build things that can kill people, we had better darn well have doubt.

My level of doubt is not likely to be present in other, "softer" disciplines. It's just the nature of the lenses through we see the world.

Cheers

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### Re: When should we doubt our knowledge?

The problem with this analogy is that there are no 2 apples that are exactly the same. Each group of 4 apples will have variations.

hahaha!! Was is about to post something along those lines. This is why I doubt mathematics applied to the "real" world. When I say doubt I mean in the most finite sense imaginable btw.

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### Re: When should we doubt our knowledge?

When I see apples are a dollar a bag, I always grab the biggest bag.

2+2=1.. Farmer A has two stacks of hay. Farmer B has two stacks of hay.
Before going to market, they combined them into 1 stack.
2+2=1..lol

I always doubt, because when I am sure of something, that's where I usually end up finding the solution to an allusive problem.

Example:
Them: It doesn't work.
Me: Is it plugged in?
Them: Of course!

Me possible: Then let's try this...
Real Me: Is there power at the plug?

Best again,
Dave :^)

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### Re: When should we doubt our knowledge?

Ursa Minimus wrote:A quick reply on one point for now:

CanadysPeak wrote:Since I am an engineer, I doubt all knowledge, all the time. It's in the specs.

Dave_Oblad wrote:When should we doubt our knowledge? "ALWAYS"!!!! (I'm also an Engineer..lol.)

Engineers doubt some things they "know" to be true. "The numbers say X is strong enough, but we'll go with X+20% to be safe". I get that. However, engineers don't doubt everything.

When should you doubt copper conducts electricity?
Or, when should you doubt that it is a good heuristic to doubt most/many/some/all things? Or how often do engineer doubt their epistemology? their memory of recent events? much of the mathematics they use?
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### Re: When should we doubt our knowledge?

Ursa Minimus wrote:I would be interested to hear anyone's take on doubting knowledge.
i doubt things when I hit a counterexample. I also tend to actively doubt things that I dislike believing. IOW where I hope I can find out it is not true. This can be personal - nobody would like the real me - to any belief about the way things are that bothers me. I call this actively doubting since it is less an experience of doubt than a decision to be skeptical, pry apart, rethink a belief if I would really prefer to have another.
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### Re: When should we doubt our knowledge?

Moreno wrote:
Ursa Minimus wrote:I would be interested to hear anyone's take on doubting knowledge.
i doubt things when I hit a counterexample. I also tend to actively doubt things that I dislike believing. IOW where I hope I can find out it is not true. This can be personal - nobody would like the real me - to any belief about the way things are that bothers me. I call this actively doubting since it is less an experience of doubt than a decision to be skeptical, pry apart, rethink a belief if I would really prefer to have another.

That doesn't sound like a good idea to me.

I think it would be better to actively try and understand things you dislike or disagree with. Maybe I have misunderstood though?

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### Re: When should we doubt our knowledge?

Moreno wrote:
Ursa Minimus wrote:I would be interested to hear anyone's take on doubting knowledge.
i doubt things when I hit a counterexample. I also tend to actively doubt things that I dislike believing. IOW where I hope I can find out it is not true. This can be personal - nobody would like the real me - to any belief about the way things are that bothers me. I call this actively doubting since it is less an experience of doubt than a decision to be skeptical, pry apart, rethink a belief if I would really prefer to have another.

That doesn't sound like a good idea to me.

I think it would be better to actively try and understand things you dislike or disagree with. Maybe I have misunderstood though?
I think you did, my lack of clarity the root. I was referring to doubting beliefs I already have that I do not like. Just to put this on a very personal level, if I believe I am worthless, even if I am convinced this is true, I will actively (at some point) call this belief out and doubt it. I may not manage to change my mind, but I notice this tendency on my part to challenge beliefs I do not like (that I already have). There are also beliefs that I challenge for this reason about the world 'out there' for similar reasons. These can be epistemological beliefs, political ones, metaphysical ones, psychological, whatever.....
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### Re: When should we doubt our knowledge?

Would you say the same is true for beliefs you love?

ie. belief in a Conscious "God". Or belief in love etc...

Basically are we all prone to stop questioning things when we are happy/content?

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### Re: When should we doubt our knowledge?

...
I see doubt as quantifiable, always present, and not in any sense bad.

CP,

I quantify doubt all the time. Via statistics.

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### Re: When should we doubt our knowledge?

wolfhnd wrote:Apples may be sold by weight and then the variation becomes relevant. You also may select the apples based on inperfections or size if sold individually. The only point I'm trying to make is that simplification of calculations while necessary to function do not replicate actual conditions.

Actual conditions? I think simplification of calculations does replicate actual conditions in critical ways.

If my wife sends me to the store to buy 12 granny smith apples, there is a correct way to fulfill that request. It's not 11, it's 11 that I claim weight as much as 12 "average" granny smith apples. If I bring home 12, I am correct, and there are consequences to that. If I bring home fewer than 12, there are consequences to that as well.

This I know. :)

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### Re: When should we doubt our knowledge?

Ok, let me see if I can generate a list here from what has been said so far, and from thinking about things this morning:

1) We should doubt when someone questions our certainty. (At least so far as to "check our math" in the case of inference or to "look at it again" in the case of observation, given CP's language).

2) We should doubt when the source of our knowledge is shown to have credibility issues (in the case of revealed knowledge, again using CP's language).

3) We should doubt when our emotions (positive or negative) are involved.

4) We should doubt when we think of/hear about/see a counterexample. Seeming disconfirming evidence, or a "thought experiment" that does not fit what we know to be the case.

5) We should doubt when actions have unexpected results. Our knowledge predicts something will happen, but it fails to happen as predicted.

6) We should doubt what we know every so often. The material world changes, our brains change. Both break down over time. So if I know my roof is solid now, I should still expect to inspect it once in a while to make sure things have not materially changed over time.

How's that? Any other heuristics to add to the list? Any problems with those? I see a few issues with some of them right off the bat:

1) Presents the problem that we obviously won't and should not treat every other person's questioning as equally valid a reason to check ourselves.

2) Do we really want to call it "knowledge" when we are basing our view of the world on someone else's expertise?

3) Presents problems when it is emotions that are the thing at issue. "I love my parents". Should that on its own be reason to doubt loving them?

6) Presents the issue of how long we should go between checks, and how that time between checks might vary for different kinds of knowledge. "I have no weed problem in my garden" might be checked every week or so. "The foundation on my house is solid" checked every few years. How do we decide how long between checks?

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### Re: When should we doubt our knowledge?

Before I write anything, I want to say that my knowledge of tex is lame and I haven't properly studied maths in years, so this post might be difficult to read and full of errors. But I want to offer a starting point at least.

Okay, I think these are the factors. Call:

2. The probability* your belief is true "p(x=t)"
3. The risk/importance** associated with getting it right/wrong "R"
4. The probability your belief is sufficiently true, ie. not worth doubting "p(x=s)"

Then I think

$p(x=s) = p(x=t)/R$

However I think it's more complicated, because of my confirmation holism, so call:

5. The collateral beliefs, whose truth value would change if p(x=t) changed, "a,b,c...n"
6. The old belief (before doubt sets in) $a_1$, the new belief*** after revision $a_2$

Then I think:

$p(x=s) = p(x=t)/{R_0}$ - $[({p({a_1}=t)>p({a_2}=t))/{R_1}$ + $({p({b_1}=t)>p({b_2}=t))/{R_2}$ + $({p({c_1}=t)>p({c_2}=t))/{R_3}$ ... + $({p({n_1}=t)>p({n_2}=t))/{R_n}]$

Finally, I think some of the more Pyrrhonic answers in this thread commit the self-excepting fallacy. To say "you should doubt everything" is to say, among other things, "you should doubt 'you should doubt everything'" and gives us nowhere to start; this doesn't just make certainty unattainable but makes all investigation and belief unattainable, including itself. It's dogmatic in its attempt not to be dogmatic.

So, in the same vein, my equation above is correct only as long as it can pass its own test; write it out twice, call them equations E and F, and substitute F into E, for $a_1$. This only needs to be done once because it's only one equation; however, the same sort of thing needs to be done with what I'm writing here. In other words, everything in this post counts as one of the collateral beliefs. However, they come with diminishing returns, so they can be dealt with by summa notation (the same way Aristotle dealt with Achilles and the Tortoise). So some subset of...

$[({p({a_1}=t)>p({a_2}=t))/{R_1}$ + $({p({b_1}=t)>p({b_2}=t))/{R_2}$ + $({p({c_1}=t)>p({c_2}=t))/{R_3}$ ... + $({p({n_1}=t)>p({n_2}=t))/{R_n}]$

...needs to be represented as****...

$\Sigma({p({x_1}=t)>p({x_2}=t))/{R_x})$

...the overall equation being...

$p(x=s) = p(x=t)/{R_0}$ - $[\Sigma({p({x_1}=t)>p({x_2}=t))/{R_x})$ + $({p({a_1}=t)>p({a_2}=t))/{R_1}$ + $({p({b_1}=t)>p({b_2}=t))/{R_2}$ + $({p({c_1}=t)>p({c_2}=t))/{R_3}$ ... + $({p({n_1}=t)>p({n_2}=t))/{R_n}]$

Sorry about my sloppy tex. I hope at least some of this post is legible, haha.

Lomax

----------

*I think the question of how to calculate this is very difficult. Xcthulhu and Lincoln gave great answers here.

** I understand that doubting takes time, particularly if the method herein is applied consciously and formally, so the rigour with which we apply the equation should be proportional to R. Since doubt can be applied in different degrees for different amounts of time, and since the "s" in "p(x=s)" is variable, I like to think this is a problem already dealt with by the equation.

*** I think it's actually a little more complicated, because we don't know what the new belief will be. Possibly the probability of the new belief being truer than the old one is something we have to infer by induction, based on the past successes and failures of our doubting escapades. This again could be done the way detailed by Xcthulhu and Lincoln.

****I don't know how to write limits in tex. Under the summa write "x=o" and over it write "p".

Lomax
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### Re: When should we doubt our knowledge?

Ursa Minimus wrote:
...
I see doubt as quantifiable, always present, and not in any sense bad.

CP,

I quantify doubt all the time. Via statistics.

Yes, exactly. I do much the same except that I imagine most social scientists use frequentist models where I tend to use probablistic ones. Perhaps I presume too much when I say what you use? If so, please correct me. I am also proactively ignorant, i.e., when I start a project, I deliberately "forget" as many facts and laws as I can, checking each as I need/apply them, and even deriving again if that seems appropriate. I don't think we disagree that much about doubt; we perhaps differ on how we use it.

CP

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### Re: When should we doubt our knowledge?

There seems to be two divergent paths this discussion can take. One is to explore the practical application of error checking of data and the other it to explore the nature of data in the context of how the brain functions.

wolfhnd
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### Re: When should we doubt our knowledge?

wolfhnd wrote:There seems to be two divergent paths this discussion can take. One is to explore the practical application of error checking of data and the other it to explore the nature of data in the context of how the brain functions.

That's an extremely good point. Recent cognitive studies on false memories (I don't have a link handy at the moment - sorry) suggest that we don't always know what we "know". That is distinctly different from simply misapplying what we really do know. That's probably worthy of a completely separate thread.

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