Just to remind us what filtration is:
Filtration
The second step is to remove from consideration aspects of the program which are not legally protectable by copyright. The analysis is done at each level of abstraction identified in the previous step. The court identifies three factors to consider during this step: elements dictated by efficiency, elements dictated by external factors, and elements taken from the public domain.[6][2]
The court explains that elements dictated by efficiency are removed from consideration based on the merger doctrine which states that a form of expression that is incidental to the idea can not be protected by copyright. In computer programs, concerns for efficiency may limit the possible ways to achieve a particular function, making a particular expression necessary to achieving the idea. In this case, the expression is not protected by copyright.[7]
Eliminating elements dictated by external factors is an application of the scènes à faire doctrine to computer programs. The doctrine holds that elements necessary for, or standard to, expression in some particular theme can not be protected by copyright.[8] Elements dictated by external factors may include hardware specifications, interoperability and compatibility requirements, design standards, demands of the market being served, and standard programming techniques.[9]
Finally, material that exists in the public domain can not be copyrighted and is also removed from the analysis.[2]
So there are 3 filtering considerations: elements dictated by efficiency, elements dictated by external factors, and elements taken from the public domain.
Chris Whittington wrote:Ridiculous irrelevant nonsense. If an "idea" determines the implementation then you SHOULD have removed the section from consideration from the comparison stage by FILTERING it out at the filtration stage.
Something you did not do, even once, in all your EVAL document process.
One example of filtering (in EVAL) for elements dictated by efficiency was the disregard of the
process used to compute the knowledge (bitboards, piece scans, ...), which indeed was one reason why EVAL_COMP worked at the abstraction level that it did.
One example of filtering elements dictated by external factors could be the non-discussion of the numeric values (for the most part), as often they can be dictated by considerations of maximising strength [or with some engines, perhaps fitting a pre-conceived notion of play of some GM] via a more mechanical process.
One example of filtering from public domain [or sufficiently common knowledge] was material scoring (1/3/3/5/9, or 100/325/325/500/975) was not included, though this would indeed seem to be an evaluation term.
I would say that if an "idea" is so precise as to determine the implementation, the idea is overly specified, and one should recede to a higher level of abstraction.
For instance, it is well-established that the moves of an individual chess game are not copyrightable. Yet a "creatively constructed" group of games is (e.g., what I think are the 100 best games of all time) is indeed copyrightable [the allowable overlap between any two such sets being dependent upon the context]. OTOH, a "noncreative" collection of games (all games from 2011 with both players over 2500 ELO) is again not copyrightable. One could have a collection specified by "All IM/GM games played in Germany from 2003-5 where a knight is sacrificed between moves 15-20, then White eventually queens his b-pawn, but Black gains a draw by perpetual check in the end" -- here the "creative content" is in making such a verbose specification, after which the collection of games therein is determined.
But I get the feeling that I wasting my time trying to explain (my understanding of) copyright law, as you seem to oppose its conclusions on philosophical grounds, at least for computer programming.