In order to keep this ''X'' simple enough to contemplate on a single pass, but still make it deep enough to cover the issues of interest at present, I limit ''X'' to having just three disjoint layers of things to worry about. The middle layer ''X''<sub>0</sub> is the initial collection of objects and signs, ''X''<sub>0</sub> = ''W''. The top layer ''Q'' is the relevant class of object qualities, ''Q'' = ''X''<sub>0</sub><math>\lessdot</math> = ''W'' <math>\cdot</math> <math>\lessdot</math>. The bottom layer ''E'' is a suitable set of object exemplars, ''E'' = ''X''<sub>0</sub><math>\gtrdot</math> = ''W'' <math>\cdot</math> <math>\gtrdot</math>. | In order to keep this ''X'' simple enough to contemplate on a single pass, but still make it deep enough to cover the issues of interest at present, I limit ''X'' to having just three disjoint layers of things to worry about. The middle layer ''X''<sub>0</sub> is the initial collection of objects and signs, ''X''<sub>0</sub> = ''W''. The top layer ''Q'' is the relevant class of object qualities, ''Q'' = ''X''<sub>0</sub><math>\lessdot</math> = ''W'' <math>\cdot</math> <math>\lessdot</math>. The bottom layer ''E'' is a suitable set of object exemplars, ''E'' = ''X''<sub>0</sub><math>\gtrdot</math> = ''W'' <math>\cdot</math> <math>\gtrdot</math>. |