Science Forums 2

[Doctordick]

Originally Posted by modest

I again apologize for the delay. I’m very interested in this topic and I do want to be very involved in the discussion. I’m, unfortunately, rebuilding my deck which is taking most of my ‘free’ time.

If I had the time, I would tell you about all the stuff I have on my agenda. Don't worry about it.

Originally Posted by modest

I really don’t have a problem, on the other hand, with assumptions so long as they are clearly recognized for what they are so that the completed model is understood to require the validity of those assumptions.

I have defined “an explanation”; if I add assumptions now, that means I have to redefined “an explanation” otherwise, there could be explanations which do not fit into my model. Thus an assumption would introduce an error; it follows, therefore, that I must be very careful not to make assumptions.

Originally Posted by modest

This is a big step for me. I didn’t realize you would be modeling a changing explanation or accounting for changing information.

I am building a model of the concept “an explanation”. As information changes, it is certainly possible that a flaw-free explanation might also change. Allowing for such change does not require a change but disallowing such change does constrain the model to explanations which do not change and that would be, in my opinion, a rather extreme assumption about explanations in general.

Originally Posted by modest

You keep stressing “no presumptions” and I’m less and less sure what you mean by that.

Every instance fulfilling the definition of “an explanation” must be included in the model.

Originally Posted by modest

I could define the future as information informing the explanation, the past as information not yet available, and the present as a change in the information being explained (i.e. information loss). That would make perfect sense to me if the arrow of time were reversed.

It seems to me that you are presuming the validity of “time” as you perceive it in your world view. You should understand that I am doing two things here. I am first defining a thing I am going to call time. Time is no more than an index explicitly denoting a change in what is known: i.e., a change in the information that flaw-free explanation is to explain. I then point out that this thing I have defined can be mapped into the common concept of time. That second step is actually not necessary but is rather little more than pointing out how that definition maps into the common concept: i.e., an excuse for calling the index “time”.

You want to use a somewhat different definition of time. I do not really understand how you intend to use your definition. First of all, do you mean to say “the future as information in forming the explanation”? If not, you will have to define what you mean by “informing”. If you are going to use the index to indicate “loss of information” then the analysis does not seem to make much sense: we start off with “all possible information” and form a flaw-free explanation. We then forget some information and this is to engender a change in that flaw-free explanation but the purpose of an explanation is to reproduce information from subsets of that information. Thus, if we have a flaw-free explanation for “all the information” and then lose some of the information, we can use that explanation to reproduce the lost information. There is thus no required change in the explanation at all.

Unless of course, we also lose the explanation with every change in information; but if that is the case, every present requires a new explanation. I don't understand what you have in mind with your definition of time and am very suspicious that you haven't thought the issue out.

Originally Posted by modest

The future would cause the present.

”Cause”? Aren't you presuming that every explanation includes causality? I think I can give you a very simple explanation which requires no causality at all. Anssi and I have discussed that explanation as a starting point. That would be the ”what is” is “what is” explanation. Causality plays no roll at all in such an explanation.

Originally Posted by modest

The probability of successfully predicting any given unknown element would be 100%.

With an explanation based on no information? I have no idea what you have in mind.

Originally Posted by modest

So, this does seem like an assumption is being made about the arrow of time pointing toward the future.

No it does not. The index “t” as defined has no direction associated with it, as defined, it is merely an index on a specific change in information. It is your explanation which assigns order to the indices.

Originally Posted by modest

I'm having a hard time seeing "past" and "future" as necessary for encompassing the possibility of the explanation changing. I could, for example, write a computer program to generate the first n primes and each instance of the program (or each iteration) it could increase n by 1 by altering itself. In this case the explanation of the data were we to examine it would be the program.

Again you are using an example where you presume to know the specific explanation, you are not concerning yourself with the general case.

Originally Posted by modest

I'm not dismissing your approach, just thinking critically about it.

I have included the idea that you are not all knowing and the creation of your explanation might be erroneous because of the the fact that there might be information you are not aware of. I am using the index “t” to handle this kind of problem. Don't worry about the fact that I call it “time”. Perhaps it does not map perfectly into your concept of time (though I doubt that) the important issue is that it handles the fact that the information on which the explanation is based can change.

Have fun -- Dick