Union
$$A \cup B =$$
{ analyst, hysteric, master, matter, motion, rest, soul, space, time, university }
Symmetric Difference
$$A \ominus B =$$
{ analyst, hysteric, master, matter, motion, rest, soul, space, time, university }
Difference
$$A - B =$$
{ matter, motion, rest, soul, space, time }
Cartesian Product
$$A \times B =$$
{ (matter, analyst),
(matter, hysteric),
(matter, master),
(matter, university),
(motion, analyst),
(motion, hysteric),
(motion, master),
(motion, university),
(rest, analyst),
(rest, hysteric),
(rest, master),
(rest, university),
(soul, analyst),
(soul, hysteric),
(soul, master),
(soul, university),
(space, analyst),
(space, hysteric),
(space, master),
(space, university),
(time, analyst),
(time, hysteric),
(time, master),
(time, university) }
Four discourses