Union
$$A \cup B =$$
{ arithmetic, astronomy, generosity, geometry, listening, metal development, music, rejoicing, respect, restraint, service, sharing of merit, teaching, understanding }
Symmetric Difference
$$A \ominus B =$$
{ arithmetic, astronomy, generosity, geometry, listening, metal development, music, rejoicing, respect, restraint, service, sharing of merit, teaching, understanding }
Cartesian Product
$$A \times B =$$
{ (arithmetic, generosity),
(arithmetic, listening),
(arithmetic, metal development),
(arithmetic, rejoicing),
(arithmetic, respect),
(arithmetic, restraint),
(arithmetic, service),
(arithmetic, sharing of merit),
(arithmetic, teaching),
(arithmetic, understanding),
(astronomy, generosity),
(astronomy, listening),
(astronomy, metal development),
(astronomy, rejoicing),
(astronomy, respect),
(astronomy, restraint),
(astronomy, service),
(astronomy, sharing of merit),
(astronomy, teaching),
(astronomy, understanding),
(geometry, generosity),
(geometry, listening),
(geometry, metal development),
(geometry, rejoicing),
(geometry, respect),
(geometry, restraint),
(geometry, service),
(geometry, sharing of merit),
(geometry, teaching),
(geometry, understanding),
(music, generosity),
(music, listening),
(music, metal development),
(music, rejoicing),
(music, respect),
(music, restraint),
(music, service),
(music, sharing of merit),
(music, teaching),
(music, understanding) }
Quadrivium