Union
$$A \cup B =$$
{ aesthetics, analysis, application, comprehension, ethics, evaluation, knowledge, logic, synthesis }
Symmetric Difference
$$A \ominus B =$$
{ aesthetics, analysis, application, comprehension, ethics, evaluation, knowledge, logic, synthesis }
Difference
$$B - A =$$
{ analysis, application, comprehension, evaluation, knowledge, synthesis }
Cartesian Product
$$A \times B =$$
{ (aesthetics, analysis),
(aesthetics, application),
(aesthetics, comprehension),
(aesthetics, evaluation),
(aesthetics, knowledge),
(aesthetics, synthesis),
(ethics, analysis),
(ethics, application),
(ethics, comprehension),
(ethics, evaluation),
(ethics, knowledge),
(ethics, synthesis),
(logic, analysis),
(logic, application),
(logic, comprehension),
(logic, evaluation),
(logic, knowledge),
(logic, synthesis) }
Charles Sanders Peirce