Author: José Carlos
Date: 14:16:12 02/19/02
Go up one level in this thread
On February 19, 2002 at 13:27:25, Christophe Theron wrote:
>On February 19, 2002 at 09:24:07, José Carlos wrote:
>
>> As it has been brought up again and I didn't give my opinion in the past, I'd
>>like to say what I think about all of that.
>> In times of Fritz 2/3, Chris was against this fast-dumb philosophy. He
>>proposed, and then implemented, something that was meant to be in the opposite
>>side, this is, slow-smart. This was his 'new paradigm' then. And it seems
>>nowadays that top programs are joining the not-so-fast-but-smarter philosophy,
>>so he was right.
>> The users have normally a very different point of view than the programmers.
>>Programmers _know_ that any program (not only chess ones) is nothing but a
>>secuence of mathematical calculations. In the very end, some 1's and 0's and the
>>hardware they 'dance' in.
>> But the users tend to see the program as if it was a person. Tend to used
>>words like 'creativity', 'aggresiveness', 'passiveness', and so on. Programs
>>don't have those characteristics, they only _seem_ to have some of them. But as
>>I said, in the end, it's nothing but a mathematical calculation that choses this
>>or that move. Believing that a program can be 'creative' is like believing that
>>it rains because the clouds are sad and cry: poetry, romanticism, creation of
>>myths.
>> Don't get me wrong, I don't say I like nor dislike poetry, that's not the
>>topic I'm trying to discuss (actually, I'm a lover of Tal's art), what I'm
>>saying is that that don't apply to computers. That's all.
>> After that, Thorsten, with his passionate and human point of view, created a
>>myth around this new paradigm, seeing in CSTal games things he had never seen in
>>other programs games, and though they happened for reasons they didn't. And I
>>understand him for doing that, it's difficult to resist.
>> But when I read Chris' post, I read the key words 'tree', 'prunning',
>>'search', 'nodes', ...
>
>
>Are you sure you are talking about the right Chris?
>
>I often use the above words in my posts.
>
>Chris Whittington (author of Chess System Tal) almost never does.
>
>
>
> Christophe
Yes, we all use those words. But I'm refferring to Thorsten post (below) about
Chris' article (I'll snip some parts to point to the words I'm talking about):
*************************************************************************
The original Chris Whittington article about the new paradigm,
alice and the mirror world of the looking glass, von manstein
and tal (as you can see from the hardware and software used in
this article, its a long time ago...):
Complete Chess System 2 - TAL
=============================
Classical paradigm
==================
[...]
They don't even know that they don't know
=========================================
[...]
An intelligent program can calculate as part of its evaluation function
whether a knight fork is available; thus the intelligent program has
this knowledge distributed evenly over the entire search tree.
^^^^^^^^^^^
[...]
Dynamic knowledge v. Combinational knowledge
============================================
[...]
12. Rxh6 { CCS2 needs only a few seconds thought to find this move }
^^^^
[...]
This game clearly shows the development and strength of the 'looking-glass'
paradigm. Genius2, a classical program, seemed to have no idea of what
was going on. CCS2 had dynamic knowledge of the strength of its attack from
move 12 on, CCS2 knew from its evaluation function;
^^^^^^^^^^
[...]
Who will be the developer ?
===========================
[...]
Search - the lazy programmer's way to avoid evaluating a position.
==================================================================
The new paradigm differs from the classical by one simple conceptual switch.
The classical paradigm makes fast and simple evaluation at each node and
generates intelligence from the search tree. The classical programmer
looks for ways to make his search more efficient and his evaluation
function simpler and faster. The 'looking-glass' paradigm makes slow and
complex evaluations at each node and prefers to prune the search tree by
^^^^^^^^^^^^^^^^^^^ ^^^^ ^^^^^ ^^^^^^^^^^^
use of this evaluation function.
[...]
I estimate that the difference in nodes per second between and extreme
^^^^^^^^^^^^^^^^
classical program and a 'looking-glass'
program will be of the order of 20-30 times, sufficient to give the
classical program an extra two plies of search (albeit with reduced
^^^^^^^^^^^^^^^^^^^
knowledge at the nodes). Thus the increased knowledge of the
'looking-glass' program has to compensate for this apparently reduced
search depth.
[...]
but our experience shows that
once breakthrough (a knowledge o f sufficient chess themes to compensate
for reduced search depth) occurs the looking-glass program begins to
consistently outplay the classical programs.
[this is interesting since it shows Chris was indeed concerned with results, not
only with the romanticism of chess]
[...]
resulting in more efficient search - more possibilities of accurate forward
^^^^^^^^^^^^^^^^^^^^^ ^^^^^^^^^^^^^^^^
pruning, resulting in smaller search trees.
^^^^^^^ ^^^^^^^^^^^^^^^^^^^^
[...]
B-Search or A-B-Search? - NO! Evaluation based or search based!
===============================================================
[...]
The looking-glass programmer condemns this dichotomy as meaningless.
The new paradigm makes the issue clear: chess programs either have simple
evaluation and generate intelligence through search, or have complex
^^^^^^^
evaluations and use limited search as a backup to cover oversights
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
and mistakes. All chess programs prune in one way or another, but
^^^^^^^^^^^^ ==============================================
looking-glass programs, with complex evaluation, are able to prune more.
=======================================================================
[...]
***************************************************************************
I think it's enough. My point is that Chris was relying on good eval smartly
applied to reduce the search tree, on the no-need to see a material advantage to
realize a 'immaterial' advantage (eval), on dynamic knowledge (eval)... But,
after all, he searched a game tree like everybody else (almost).
José C.
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