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Subject: Re: guilty until probed the opposite

Author: Uri Blass

Date: 16:08:05 05/28/05

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On May 28, 2005 at 18:38:51, Cesar Contreras wrote:

>To all of you:
>It seems to me like a witch hunting, i don't mean it's a bad thing to search for
>justice, what i mean it's that many are taking conclusions too quickly. I don't
>say "Fafis it's not a clone", but if it is, the evidence it's not conclusive.
>In the other hand, i see many efford (people/hours) in order to probe fafis it's
>a clone ... i hope there are at least some people thinking in some ways to probe
>it is not a clone... that can be called justice.
>"guilty until probed the opposite" it's just plain bad (some are taking out
>fafis from their tournaments). Why don't wait a little more?  why the hurry?
>Some things i like to add:
>- I'ts important to know the names of the other 3 engines  that made the same
>moves as crafty in the draw game. The others must be clones also or this
>evidence it's irrelevant.

I agree that it is important to know the name of the other engines.

>- I'ts important to know the name of the other engine that made the same move as
>crafty in the mate on one. The other must be a clone also or this evidence it's

I also agree.

>- Crafty it's a center of knowledge in chess programming, so having programs
>that behave the same in some aspects or some positions don't seem to me that

No Crafty is not the center of knowledge.

>- The strings "captured a king" and "feature rejected by xboard" are not a good
>- The code needed to generate moves, parse FEN it's a little part of a chess
>program, you can't say it's a clone based on that little parts.

I do not agree that the code of generating moves is a little part.
The data structure that is used for the move generator is used also for other

>- The virus thing can happen to all we engine authors, we are confident in our
>antivirus, but virus are first then antivirus, and some virus simply desactivate
>the antivirus. I think some pleople here just closing their mind, i can imagine
>a loot of ways the virus can get into the exe  (worm mutation, worm
>modification, bad information from antivirus companies). You can suspect that
>Rafael append the worm himself, but you can't be for sure.
>As an engine author myself i think (IMHO) that the evidence it's not conclusive,
>i can imagine it's not dificult to find similar behaviors on some aspects on
>very diferent engines.
>With all my respect i think you must be more carefull when you release this kind
>of information, it must be released when you have enought evidence to probe it.
>Maybe you are rigth and Fafis it is a clone, but maybe not and one person it's
>To the engine authors:
>- How many % of code make an engine a clone?
>- How many lines of code make an engine a clone?
>- How many % of fafis it's crafty code?
>- then how do you know it's a clone?
>- suposing you got conclusive evidence tell that Move generator and FEN parser
>it's crafty code? how mutch % of the code it is?

Not important.
It is illegal to do it.

>- How do you feel if your engine it's declared a clone when you know it's not?
>You know you took some ideas from here or from there, but you know it's not a
>- What it's the way to clean your name?

I am not afraid of it.
I am quiet sure that people will never find big similiarities like they found in
Fafis or Partiot to some free source code.

Movei has a lot of original datastructure that was not copied from another
program so I do not believe that it can show the same behaviour like another

probaility is so small that it is practically 0.


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