Union
$$A \cup B =$$
{ application, audio, example, font, image, message, metaphysical, model, multipart, positivity, text, theological, video }
Symmetric Difference
$$A \ominus B =$$
{ application, audio, example, font, image, message, metaphysical, model, multipart, positivity, text, theological, video }
Difference
$$B - A =$$
{ application, audio, example, font, image, message, model, multipart, text, video }
Cartesian Product
$$A \times B =$$
{ (metaphysical, application),
(metaphysical, audio),
(metaphysical, example),
(metaphysical, font),
(metaphysical, image),
(metaphysical, message),
(metaphysical, model),
(metaphysical, multipart),
(metaphysical, text),
(metaphysical, video),
(positivity, application),
(positivity, audio),
(positivity, example),
(positivity, font),
(positivity, image),
(positivity, message),
(positivity, model),
(positivity, multipart),
(positivity, text),
(positivity, video),
(theological, application),
(theological, audio),
(theological, example),
(theological, font),
(theological, image),
(theological, message),
(theological, model),
(theological, multipart),
(theological, text),
(theological, video) }
Law of three stages