Union
$$A \cup B =$$
{ aristocracy, concomitant variations, democracy, difference, direct agreement, joint agreement and difference, oligarchy, residue, timocracy, tyranny }
Symmetric Difference
$$A \ominus B =$$
{ aristocracy, concomitant variations, democracy, difference, direct agreement, joint agreement and difference, oligarchy, residue, timocracy, tyranny }
Difference
$$A - B =$$
{ concomitant variations, difference, direct agreement, joint agreement and difference, residue }
Cartesian Product
$$A \times B =$$
{ (concomitant variations, aristocracy),
(concomitant variations, democracy),
(concomitant variations, oligarchy),
(concomitant variations, timocracy),
(concomitant variations, tyranny),
(difference, aristocracy),
(difference, democracy),
(difference, oligarchy),
(difference, timocracy),
(difference, tyranny),
(direct agreement, aristocracy),
(direct agreement, democracy),
(direct agreement, oligarchy),
(direct agreement, timocracy),
(direct agreement, tyranny),
(joint agreement and difference, aristocracy),
(joint agreement and difference, democracy),
(joint agreement and difference, oligarchy),
(joint agreement and difference, timocracy),
(joint agreement and difference, tyranny),
(residue, aristocracy),
(residue, democracy),
(residue, oligarchy),
(residue, timocracy),
(residue, tyranny) }
Mill's Methods