The Chess Variant Pages

This page is written by the game's inventor, Uli Schwekendiek.

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Bn Em wrote on 2021-03-15 UTC


Re Duke's variant and patent: whilst it was, indeed, probably an exercise in extending the patent's scope, I'd argue that technically he did describe this variant first (and strictly speaking patents are a different thing from copyright, and I'm not convinced that someone patenting a new set of chords (perhaps in some unusual tuning?) that wasn't in prior use coudn't in fact claim a breach of patent on anything using them, though ofc IANAL) — however you rightly point out that he came to different conclusions, and that merely having described it as part of a set of possibilities doesn't mean that he should be credited for it (H. G. Muller's analogy with integers is apt here). My main point was that it's more interesting (at least for me ☺︎) to acknowledge the commonalities (as you have now, indeed, done) and explore the differences within that than to insist that everything is unique and special in itself.

Also I agree, naming things is hard (which is partly why it was uncanny that you ended up with the same name as Duke did).


Strictly speaking Kestrel has been used (by Gilman, predictably enough) for a piece — just not in any games. It's the compound of (stepping) Falcon and Kite (the latter moving as falcon but replacing orthogonal steps with ‘nonstandard’ (i.e. √3) diagonal ones) according to M&B13.

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