Why five fingures and no thumb?

On first seeing the plate its overall aspect screamed "Picasso" to me. On second glance two features confirmed my initial thoughts.

Firstly, the structural compostion of the artwork.

And secondly, specific detail of its execution.

Consider for instance the knight's left hand - show in detail above. It's a direct take from the clarinet player in Picasso's 1921 painting entitled "Three Musicians". Picasso frequently use this device in many cubist, surreal and portraiture works thoughout the 1920's and 1930's. The latest painting that I'm aware of, in which he used a similar representation of a hand, was in the work entitled "Bust of a Man" (12 February 1972).
Having successfully depicted hands in this way for at least fifty years, it would be little surprise if he utilised the motif during the many years he produced ceramics.

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