When a matrix M is subjected to a rule R, we define the APPLICABILITY OF R TO M as follows: (4) If SD(R) is a sub-matrix of M, then M meets the conditions of R; thus R APPLIES to M, and (the minimun required number of) features are added or changed in M until SC(R) is also a sub-matrix of M. (5) If SD(R) is distinct from M, then M does not meet the conditions of R; thus R FAILS TO APPLY to M, and M passes through unchanged [...]: a rule R FAILS to apply to (i.e. has NO effect on) a matrix M if SD(R) is incomparable with M.
- Stanley (2004), a pag.64