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Re: "what generally happens here"

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Nick Thompson

Re: "what generally happens here"

Ah, Phil. If you are correct that the answer to "what generally happens here?" is regarded by some as an "explanation", then the source of the confusion underlying this conversation becomes immediately evident.

But who would believe such a silly thing?!!!!! "What generally happens here" is just a summary statement of past experience One cannot rationally pass from such a summary of past events to any statement about the future without a theory of some sort that models the world as the sort of place where "what generally has happened"" is what happens in the future.

Could it be the case that all this talk about the evils of prediction has occured because Epstein and a few others woke up yesterday to the Fallacy of Induction?!!!! Oh, my. Say it isnt so!

Nicholas S. Thompson

Emeritus Professor of Psychology and Ethology,

Clark University ([hidden email])

----- Original Message -----

From: [hidden email]

To: [hidden email];[hidden email]

Sent: 12/2/2008 8:28:03 AM

Subject: RE: [FRIAM] Wedtech to Friam: earthquakes

Theres always the difference between the kind of question you ask and the type of prediction and explanation for it.    For example, you might ask either what generally happens here or what is happening here.   The first asks for a simple explanation and a rule of thumb type prediction.   It might be helpful for responding to the second question, or not.   The second question is more about individual complex systems in a particular circumstance requiring one to start from the limited information that raises the question and to go to the trouble of expanding your understanding while exploring possible patterns in the environment until you find one that seems to fit.

I think there are lots of differences between any kind of explanatory causation and the instrumental causes.    Maybe explanations become useless if they try to include all the complexity of the instrumental processes, but also often loose their value by ignoring the underlying complexity too.

Re: earth quakes, I went to a lecture at Columbia recently that was just great on the physics of slow slips in a shearing crust, large horizontal zones of gradual internal tearing within the crust, having leading vibration events and propagation fronts, etc.

Phil Henshaw

From: [hidden email] [mailto:[hidden email]] On Behalf Of Nicholas Thompson
Sent: Monday, December 01, 2008 3:04 PM
To: [hidden email]
Subject: [FRIAM] Wedtech to Friam: earthquakes

Dear All,

We have been having a discussion on a SF Site called Wedtech about the relationship between explanation, simulation, and prediction. If you want to get a sense of the starting point of that discussion, have a look at Josh Epstein's forum entry in the current JASSS, which seems to be just about as wrong headed as a piece of writing can be. In it, he makes a radical separation between prediction and explanation, implying that the quality, accuracy, scope, and precision of predictions that arise from an explanation is no measure of that explanation's value.

In the course of trying to discover where such a silly idea might have come from, I was led to literatures in economics and geophysics where, indeed, the word "prediction" has taken on a negative tone. These seem to be both fields in which the need for knowledge about the future has overwhelmed people's need to understand the phenomenon, so that predictive activities have way outrun theory.

However, acknowledging the problem in these literatures is not the same thing as making a principled claim that prediction has nothing to do with explanation.

In the course of thinking about these matters, I have stumbled on an extraordinary website packed with simulations done by people at the USGS in Menlo Park California. the page is http://quake.usgs.gov/research/deformation/modeling/animations/.   I commend to you particularly, the simulations done on teh Anatolian Fault in Turkey (BELOW the stuff on california) and ask you to ponder whether the mix of simulatoin, explanation, and predicition is appropriate here. I suggest you start at the top of the Anatolian series and move from simulation to simulation using the link provided at the bottom right of each simulation. Stress buildup and stress release are represented by red and blue colors respectively and the theory is one of stress propogation.   I would love to know where the colors come from i.e., how stress is measured. If there is no independent measure of stress, then, as in psychology, the notion of stress is just covert adhockery.

Please let me (us) know what you think.

Nick

Nicholas S. Thompson

Emeritus Professor of Psychology and Ethology,

Clark University ([hidden email])

============================================================
FRIAM Applied Complexity Group listserv
Meets Fridays 9a-11:30 at cafe at St. John's College
lectures, archives, unsubscribe, maps at http://www.friam.org

Phil Henshaw-2

Re: "what generally happens here"

Why prediction fails does not seem to be just believing your own script.. as it were. I’m suggesting that “a theory of some sort” is generally the same thing as “a statement of what generally has happened”. The real question may be sort of the opposite of “but who would believe such a thing?!!!!!” since believing in a theory with little or no way of checking how what is actually happening is different from it, seems to be nearly everyone’s preference. To do the latter you need to maintain the open questions of your induction, and not cast them off as soon as you have made something useful with it.

So I don’t think it’s a “fallacy of induction” per se. I think it’s more just that any handy tool can be greatly misused if you don’t keep asking “how does it apply here”. There is also an all too common preference for absolutist rules that contributes to our dodging any information about how they might not quite apply too… but I guess that’s not just a matter of clumsiness.

So, is that saying “it is so” or “it isn’t so”, I’m confused… ;-)

Phil Henshaw

From: Nicholas Thompson [mailto:[hidden email]]
Sent: Tuesday, December 02, 2008 12:32 PM
To: Phil Henshaw; The Friday Morning Applied Complexity Coffee Group
Cc: [hidden email]; [hidden email]
Subject: RE: "what generally happens here"

Could it be the case that all this talk about the evils of prediction has occured because Epstein and a few others woke up yesterday to the Fallacy of Induction?!!!! Oh, my. Say it isnt so!

Nicholas S. Thompson

Emeritus Professor of Psychology and Ethology,

Clark University ([hidden email])

----- Original Message -----

From: [hidden email]

To: [hidden email];[hidden email]

Sent: 12/2/2008 8:28:03 AM

Subject: RE: [FRIAM] Wedtech to Friam: earthquakes

There’s always the difference between the kind of question you ask and the type of prediction and explanation for it.    For example, you might ask either “what generally happens here” or “what is happening here”.   The first asks for a simple explanation and a rule of thumb type prediction.   It might be helpful for responding to the second question, or not.   The second question is more about individual complex systems in a particular circumstance requiring one to start from the limited information that raises the question and to go to the trouble of expanding your understanding while exploring possible patterns in the environment until you find one that seems to fit.

I think there are lots of differences between any kind of explanatory causation and the instrumental causes.    Maybe explanations become useless if they try to include all the complexity of the instrumental processes, but also often loose their value by ignoring the underlying complexity too.

Re: earth quakes, I went to a lecture at Columbia recently that was just great on the physics of ‘slow slips’ in a shearing crust, large horizontal zones of gradual internal tearing within the crust, having leading vibration events and propagation fronts, etc.

Phil Henshaw

From: [hidden email] [mailto:[hidden email]] On Behalf Of Nicholas Thompson
Sent: Monday, December 01, 2008 3:04 PM
To: [hidden email]
Subject: [FRIAM] Wedtech to Friam: earthquakes

Dear All,

We have been having a discussion on a SF Site called Wedtech about the relationship between explanation, simulation, and prediction. If you want to get a sense of the starting point of that discussion, have a look at Josh Epstein's forum entry in the current JASSS, which seems to be just about as wrong headed as a piece of writing can be. In it, he makes a radical separation between prediction and explanation, implying that the quality, accuracy, scope, and precision of predictions that arise from an explanation is no measure of that explanation's value.

In the course of trying to discover where such a silly idea might have come from, I was led to literatures in economics and geophysics where, indeed, the word "prediction" has taken on a negative tone. These seem to be both fields in which the need for knowledge about the future has overwhelmed people's need to understand the phenomenon, so that predictive activities have way outrun theory.

However, acknowledging the problem in these literatures is not the same thing as making a principled claim that prediction has nothing to do with explanation.

In the course of thinking about these matters, I have stumbled on an extraordinary website packed with simulations done by people at the USGS in Menlo Park California. the page is http://quake.usgs.gov/research/deformation/modeling/animations/.   I commend to you particularly, the simulations done on teh Anatolian Fault in Turkey (BELOW the stuff on california) and ask you to ponder whether the mix of simulatoin, explanation, and predicition is appropriate here. I suggest you start at the top of the Anatolian series and move from simulation to simulation using the link provided at the bottom right of each simulation. Stress buildup and stress release are represented by red and blue colors respectively and the theory is one of stress propogation.   I would love to know where the colors come from i.e., how stress is measured. If there is no independent measure of stress, then, as in psychology, the notion of stress is just covert adhockery.

Please let me (us) know what you think.

Nick

Nicholas S. Thompson

Emeritus Professor of Psychology and Ethology,

Clark University ([hidden email])

Nick Thompson

Re: "what generally happens here"

In reply to this post by Nick Thompson

Phil,

I strongly disagree.

The difference between an explanation and a generalization is, plainly, a model of the process being summarized in the generalization. Explanations inevitably invoke metaphysics ... not only a generalization but a vision, picture, a understanding of how the world is. Even if all swans WERE white, the fact that this bird was a swan would not, to me at least, be a satisfying explanation for why it is white. I guess this is where I part company with Hempel. An explanation, by its very nature, requires us to paint the roof of the chapel from our imaginations. The explantion is what accounts for the generality, not the generality itself. It is the reason WHY all swans are white, not the "fact" that they are. In my world, anyway, explanations speak of causes.

Nick

Nicholas S. Thompson

Emeritus Professor of Psychology and Ethology,

Clark University ([hidden email])

----- Original Message -----

From: [hidden email]

To: [hidden email];[hidden email]
Cc: [hidden email]; [hidden email]

Sent: 12/2/2008 11:09:33 AM

Subject: RE: "what generally happens here"

Why prediction fails does not seem to be just believing your own script.. as it were.    Im suggesting that a theory of some sort is generally the same thing as a statement of what generally has happened.    The real question may be sort of the opposite of but who would believe such a thing?!!!!! since believing in a theory with little or no way of checking how what is actually happening is different from it, seems to be nearly everyones preference.   To do the latter you need to maintain the open questions of your induction, and not cast them off as soon as you have made something useful with it.

So I dont think its a fallacy of induction per se.     I think its more just that any handy tool can be greatly misused if you dont keep asking how does it apply here.     There is also an all too common preference for absolutist rules that contributes to our dodging any information about how they might not quite apply too but I guess thats not just a matter of clumsiness.

So, is that saying it is so or it isnt so, Im confused ;-)

Phil Henshaw

From: Nicholas Thompson [mailto:[hidden email]]
Sent: Tuesday, December 02, 2008 12:32 PM
To: Phil Henshaw; The Friday Morning Applied Complexity Coffee Group
Cc: [hidden email]; [hidden email]
Subject: RE: "what generally happens here"

Ah, Phil. If you are correct that the answer to "what generally happens here?" is regarded by some as an "explanation", then the source of the confusion underlying this conversation becomes immediately evident.

But who would believe such a silly thing?!!!!! "What generally happens here" is just a summary statement of past experience One cannot rationally pass from such a summary of past events to any statement about the future without a theory of some sort that models the world as the sort of place where "what generally has happened"" is what happens in the future.

Could it be the case that all this talk about the evils of prediction has occured because Epstein and a few others woke up yesterday to the Fallacy of Induction?!!!! Oh, my. Say it isnt so!

N

Nicholas S. Thompson

Emeritus Professor of Psychology and Ethology,

Clark University ([hidden email])

----- Original Message -----

From: [hidden email]

To: [hidden email];[hidden email]

Sent: 12/2/2008 8:28:03 AM

Subject: RE: [FRIAM] Wedtech to Friam: earthquakes

Theres always the difference between the kind of question you ask and the type of prediction and explanation for it.    For example, you might ask either what generally happens here or what is happening here.   The first asks for a simple explanation and a rule of thumb type prediction.   It might be helpful for responding to the second question, or not.   The second question is more about individual complex systems in a particular circumstance requiring one to start from the limited information that raises the question and to go to the trouble of expanding your understanding while exploring possible patterns in the environment until you find one that seems to fit.

I think there are lots of differences between any kind of explanatory causation and the instrumental causes.    Maybe explanations become useless if they try to include all the complexity of the instrumental processes, but also often loose their value by ignoring the underlying complexity too.

Re: earth quakes, I went to a lecture at Columbia recently that was just great on the physics of slow slips in a shearing crust, large horizontal zones of gradual internal tearing within the crust, having leading vibration events and propagation fronts, etc.

Phil Henshaw

From: [hidden email] [mailto:[hidden email]] On Behalf Of Nicholas Thompson
Sent: Monday, December 01, 2008 3:04 PM
To: [hidden email]
Subject: [FRIAM] Wedtech to Friam: earthquakes

Dear All,

We have been having a discussion on a SF Site called Wedtech about the relationship between explanation, simulation, and prediction. If you want to get a sense of the starting point of that discussion, have a look at Josh Epstein's forum entry in the current JASSS, which seems to be just about as wrong headed as a piece of writing can be. In it, he makes a radical separation between prediction and explanation, implying that the quality, accuracy, scope, and precision of predictions that arise from an explanation is no measure of that explanation's value.

In the course of trying to discover where such a silly idea might have come from, I was led to literatures in economics and geophysics where, indeed, the word "prediction" has taken on a negative tone. These seem to be both fields in which the need for knowledge about the future has overwhelmed people's need to understand the phenomenon, so that predictive activities have way outrun theory.

However, acknowledging the problem in these literatures is not the same thing as making a principled claim that prediction has nothing to do with explanation.

In the course of thinking about these matters, I have stumbled on an extraordinary website packed with simulations done by people at the USGS in Menlo Park California. the page is http://quake.usgs.gov/research/deformation/modeling/animations/.   I commend to you particularly, the simulations done on teh Anatolian Fault in Turkey (BELOW the stuff on california) and ask you to ponder whether the mix of simulatoin, explanation, and predicition is appropriate here. I suggest you start at the top of the Anatolian series and move from simulation to simulation using the link provided at the bottom right of each simulation. Stress buildup and stress release are represented by red and blue colors respectively and the theory is one of stress propogation.   I would love to know where the colors come from i.e., how stress is measured. If there is no independent measure of stress, then, as in psychology, the notion of stress is just covert adhockery.

Please let me (us) know what you think.

Nick

Nicholas S. Thompson

Emeritus Professor of Psychology and Ethology,

Clark University ([hidden email])

Carl Tollander

Re: "what generally happens here"

In reply to this post by Phil Henshaw-2

A robust theory would then be one that is accessible by many explanations, unifying them by showing how they could make equivalent paths through an heuristic. It would serve to maintain open questions by allowing them to be more local. A theory with only one explanation would be a crappy theory; mistakes would propagate more globally instead of getting metabolized more locally.

I liked Phil's second question, which I take to lead more towards using models to make sense of the present, rather than to "predict" ;

The second question is more about individual complex systems in a particular circumstance requiring one to start from the limited information that raises the question and to go to the trouble of expanding your understanding while exploring possible patterns in the environment until you find one that seems to fit.

Another one would be "who's environment?", which I think leads one back to ontology formation/niche construction. Is it not so much that prediction is bad but rather that it is quaint for the types of questions we want/need to ask?

Carl

Phil Henshaw wrote:

Why prediction fails does not seem to be just believing your own script.. as it were.    I’m suggesting that “a theory of some sort” is generally the same thing as “a statement of what generally has happened”.    The real question may be sort of the opposite of “but who would believe such a thing?!!!!!” since believing in a theory with little or no way of checking how what is actually happening is different from it, seems to be nearly everyone’s preference.   To do the latter you need to maintain the open questions of your induction, and not cast them off as soon as you have made something useful with it.

So I don’t think it’s a “fallacy of induction” per se.     I think it’s more just that any handy tool can be greatly misused if you don’t keep asking “how does it apply here”.     There is also an all too common preference for absolutist rules that contributes to our dodging any information about how they might not quite apply too… but I guess that’s not just a matter of clumsiness.

So, is that saying “it is so” or “it isn’t so”, I’m confused… ;-)

Phil Henshaw

From: Nicholas Thompson [[hidden email]]
Sent: Tuesday, December 02, 2008 12:32 PM
To: Phil Henshaw; The Friday Morning Applied Complexity Coffee Group
Cc: [hidden email]; [hidden email]
Subject: RE: "what generally happens here"

Ah, Phil. If you are correct that the answer to "what generally happens here?" is regarded by some as an "explanation", then the source of the confusion underlying this conversation becomes immediately evident.

But who would believe such a silly thing?!!!!! "What generally happens here" is just a summary statement of past experience One cannot rationally pass from such a summary of past events to any statement about the future without a theory of some sort that models the world as the sort of place where "what generally has happened"" is what happens in the future.

Could it be the case that all this talk about the evils of prediction has occured because Epstein and a few others woke up yesterday to the Fallacy of Induction?!!!! Oh, my. Say it isnt so!

N

Nicholas S. Thompson

Emeritus Professor of Psychology and Ethology,

Clark University ([hidden email])

----- Original Message -----

From: [hidden email]

To: [hidden email];[hidden email]

Sent: 12/2/2008 8:28:03 AM

Subject: RE: [FRIAM] Wedtech to Friam: earthquakes

There’s always the difference between the kind of question you ask and the type of prediction and explanation for it.    For example, you might ask either “what generally happens here” or “what is happening here”.   The first asks for a simple explanation and a rule of thumb type prediction.   It might be helpful for responding to the second question, or not.   The second question is more about individual complex systems in a particular circumstance requiring one to start from the limited information that raises the question and to go to the trouble of expanding your understanding while exploring possible patterns in the environment until you find one that seems to fit.

I think there are lots of differences between any kind of explanatory causation and the instrumental causes.    Maybe explanations become useless if they try to include all the complexity of the instrumental processes, but also often loose their value by ignoring the underlying complexity too.

Re: earth quakes, I went to a lecture at Columbia recently that was just great on the physics of ‘slow slips’ in a shearing crust, large horizontal zones of gradual internal tearing within the crust, having leading vibration events and propagation fronts, etc.

Phil Henshaw

From: [hidden email] [[hidden email]] On Behalf Of Nicholas Thompson
Sent: Monday, December 01, 2008 3:04 PM
To: [hidden email]
Subject: [FRIAM] Wedtech to Friam: earthquakes

Dear All,

We have been having a discussion on a SF Site called Wedtech about the relationship between explanation, simulation, and prediction. If you want to get a sense of the starting point of that discussion, have a look at Josh Epstein's forum entry in the current JASSS, which seems to be just about as wrong headed as a piece of writing can be. In it, he makes a radical separation between prediction and explanation, implying that the quality, accuracy, scope, and precision of predictions that arise from an explanation is no measure of that explanation's value.

In the course of trying to discover where such a silly idea might have come from, I was led to literatures in economics and geophysics where, indeed, the word "prediction" has taken on a negative tone. These seem to be both fields in which the need for knowledge about the future has overwhelmed people's need to understand the phenomenon, so that predictive activities have way outrun theory.

However, acknowledging the problem in these literatures is not the same thing as making a principled claim that prediction has nothing to do with explanation.

In the course of thinking about these matters, I have stumbled on an extraordinary website packed with simulations done by people at the USGS in Menlo Park California. the page is http://quake.usgs.gov/research/deformation/modeling/animations/.   I commend to you particularly, the simulations done on teh Anatolian Fault in Turkey (BELOW the stuff on california) and ask you to ponder whether the mix of simulatoin, explanation, and predicition is appropriate here. I suggest you start at the top of the Anatolian series and move from simulation to simulation using the link provided at the bottom right of each simulation. Stress buildup and stress release are represented by red and blue colors respectively and the theory is one of stress propogation.   I would love to know where the colors come from i.e., how stress is measured. If there is no independent measure of stress, then, as in psychology, the notion of stress is just covert adhockery.

Please let me (us) know what you think.

Nick

Nicholas S. Thompson

Emeritus Professor of Psychology and Ethology,

Clark University ([hidden email])
============================================================
FRIAM Applied Complexity Group listserv
Meets Fridays 9a-11:30 at cafe at St. John's College
lectures, archives, unsubscribe, maps at http://www.friam.org

Phil Henshaw-2

Re: "what generally happens here"

In reply to this post by Nick Thompson

Nick,

Well, it’s hard to follow all the different conventions people have for the terms they use. I agree that a generalization implies a broader and more inclusive way of explaining things, but I find that most generalizations are rather particular to the assumptions of the person or the community that finds them inclusively explanatory… so… I keep having to attach the little foot note “for the way the question was asked”. As they say “y” is a crooked letter. :-) but experience suggests there are some explanations that have very great generality, and other that have less, though it’s hard to tell which much of the time. Asking about ‘causes’ doesn’t always narrow it down for me.

I think it’s a little less confusing to ask “how” something happened rather than “why” as the causal question. You tend to use wild leaps of association that way… :-) I still endlessly stumble into how language equates different metaphors in a speaker’s and listener’s mind with processes in the physical world we occupy in common, making it unusually difficult to be clear about whether our words are referring to anything in common a listener and speaker might independently consider.

I think you were recently puzzling over why it’s so very hard to communicate anything in particular. Do you think this mixed reference problem might have something to do with that?

Phil Henshaw

From: Nicholas Thompson [mailto:[hidden email]]
Sent: Tuesday, December 02, 2008 1:57 PM
To: Phil Henshaw; The Friday Morning Applied Complexity Coffee Group
Cc: [hidden email]; [hidden email]
Subject: RE: "what generally happens here"

Phil,

I strongly disagree.

Nick

Nicholas S. Thompson

Emeritus Professor of Psychology and Ethology,

Clark University ([hidden email])

----- Original Message -----

From: [hidden email]

To: [hidden email];[hidden email]

Cc: [hidden email]; [hidden email]

Sent: 12/2/2008 11:09:33 AM

Subject: RE: "what generally happens here"

Why prediction fails does not seem to be just believing your own script.. as it were.    I’m suggesting that “a theory of some sort” is generally the same thing as “a statement of what generally has happened”.    The real question may be sort of the opposite of “but who would believe such a thing?!!!!!” since believing in a theory with little or no way of checking how what is actually happening is different from it, seems to be nearly everyone’s preference.   To do the latter you need to maintain the open questions of your induction, and not cast them off as soon as you have made something useful with it.

So I don’t think it’s a “fallacy of induction” per se.     I think it’s more just that any handy tool can be greatly misused if you don’t keep asking “how does it apply here”.     There is also an all too common preference for absolutist rules that contributes to our dodging any information about how they might not quite apply too… but I guess that’s not just a matter of clumsiness.

So, is that saying “it is so” or “it isn’t so”, I’m confused… ;-)

Phil Henshaw

From: Nicholas Thompson [mailto:[hidden email]]
Sent: Tuesday, December 02, 2008 12:32 PM
To: Phil Henshaw; The Friday Morning Applied Complexity Coffee Group
Cc: [hidden email]; [hidden email]
Subject: RE: "what generally happens here"

Ah, Phil. If you are correct that the answer to "what generally happens here?" is regarded by some as an "explanation", then the source of the confusion underlying this conversation becomes immediately evident.

But who would believe such a silly thing?!!!!! "What generally happens here" is just a summary statement of past experience One cannot rationally pass from such a summary of past events to any statement about the future without a theory of some sort that models the world as the sort of place where "what generally has happened"" is what happens in the future.

Could it be the case that all this talk about the evils of prediction has occured because Epstein and a few others woke up yesterday to the Fallacy of Induction?!!!! Oh, my. Say it isnt so!

N

Nicholas S. Thompson

Emeritus Professor of Psychology and Ethology,

Clark University ([hidden email])

----- Original Message -----

From: [hidden email]

To: [hidden email];[hidden email]

Sent: 12/2/2008 8:28:03 AM

Subject: RE: [FRIAM] Wedtech to Friam: earthquakes

There’s always the difference between the kind of question you ask and the type of prediction and explanation for it.    For example, you might ask either “what generally happens here” or “what is happening here”.   The first asks for a simple explanation and a rule of thumb type prediction.   It might be helpful for responding to the second question, or not.   The second question is more about individual complex systems in a particular circumstance requiring one to start from the limited information that raises the question and to go to the trouble of expanding your understanding while exploring possible patterns in the environment until you find one that seems to fit.

I think there are lots of differences between any kind of explanatory causation and the instrumental causes.    Maybe explanations become useless if they try to include all the complexity of the instrumental processes, but also often loose their value by ignoring the underlying complexity too.

Re: earth quakes, I went to a lecture at Columbia recently that was just great on the physics of ‘slow slips’ in a shearing crust, large horizontal zones of gradual internal tearing within the crust, having leading vibration events and propagation fronts, etc.

Phil Henshaw

From: [hidden email] [mailto:[hidden email]] On Behalf Of Nicholas Thompson
Sent: Monday, December 01, 2008 3:04 PM
To: [hidden email]
Subject: [FRIAM] Wedtech to Friam: earthquakes

Dear All,

We have been having a discussion on a SF Site called Wedtech about the relationship between explanation, simulation, and prediction. If you want to get a sense of the starting point of that discussion, have a look at Josh Epstein's forum entry in the current JASSS, which seems to be just about as wrong headed as a piece of writing can be. In it, he makes a radical separation between prediction and explanation, implying that the quality, accuracy, scope, and precision of predictions that arise from an explanation is no measure of that explanation's value.

In the course of trying to discover where such a silly idea might have come from, I was led to literatures in economics and geophysics where, indeed, the word "prediction" has taken on a negative tone. These seem to be both fields in which the need for knowledge about the future has overwhelmed people's need to understand the phenomenon, so that predictive activities have way outrun theory.

However, acknowledging the problem in these literatures is not the same thing as making a principled claim that prediction has nothing to do with explanation.

In the course of thinking about these matters, I have stumbled on an extraordinary website packed with simulations done by people at the USGS in Menlo Park California. the page is http://quake.usgs.gov/research/deformation/modeling/animations/.   I commend to you particularly, the simulations done on teh Anatolian Fault in Turkey (BELOW the stuff on california) and ask you to ponder whether the mix of simulatoin, explanation, and predicition is appropriate here. I suggest you start at the top of the Anatolian series and move from simulation to simulation using the link provided at the bottom right of each simulation. Stress buildup and stress release are represented by red and blue colors respectively and the theory is one of stress propogation.   I would love to know where the colors come from i.e., how stress is measured. If there is no independent measure of stress, then, as in psychology, the notion of stress is just covert adhockery.

Please let me (us) know what you think.

Nick

Nicholas S. Thompson

Emeritus Professor of Psychology and Ethology,

Clark University ([hidden email])