Say I have a set that has mixed comparable and incomparable elements.
$$S_C = \{ 1, 2, 3 \}$$
$$S_I = \{, \}$$
$$...$$
$$ S_M = S_C \cup S_I \cup ... $$
$$ where $$
$$S_J \in S_I || S_M\setminus S_j $$
By convention, are all elements of $S_J$ said to be both maximal and minimal on the set $S_M$?