Union
$$A \cup B =$$
{ anal, efficient (creator), final (function), formal (design), genital, latency, material, oral, phallic }
Symmetric Difference
$$A \ominus B =$$
{ anal, efficient (creator), final (function), formal (design), genital, latency, material, oral, phallic }
Difference
$$A - B =$$
{ anal, genital, latency, oral, phallic }
Difference
$$B - A =$$
{ efficient (creator), final (function), formal (design), material }
Cartesian Product
$$A \times B =$$
{ (anal, efficient (creator)),
(anal, final (function)),
(anal, formal (design)),
(anal, material),
(genital, efficient (creator)),
(genital, final (function)),
(genital, formal (design)),
(genital, material),
(latency, efficient (creator)),
(latency, final (function)),
(latency, formal (design)),
(latency, material),
(oral, efficient (creator)),
(oral, final (function)),
(oral, formal (design)),
(oral, material),
(phallic, efficient (creator)),
(phallic, final (function)),
(phallic, formal (design)),
(phallic, material) }
Psychosexual development