Union
$$A \cup B =$$
{ artha, concrete operational, dharma, formal operational, kama, moksha, pre-operational, sensorimotor }
Symmetric Difference
$$A \ominus B =$$
{ artha, concrete operational, dharma, formal operational, kama, moksha, pre-operational, sensorimotor }
Difference
$$A - B =$$
{ concrete operational, formal operational, pre-operational, sensorimotor }
Difference
$$B - A =$$
{ artha, dharma, kama, moksha }
Cartesian Product
$$A \times B =$$
{ (concrete operational, artha),
(concrete operational, dharma),
(concrete operational, kama),
(concrete operational, moksha),
(formal operational, artha),
(formal operational, dharma),
(formal operational, kama),
(formal operational, moksha),
(pre-operational, artha),
(pre-operational, dharma),
(pre-operational, kama),
(pre-operational, moksha),
(sensorimotor, artha),
(sensorimotor, dharma),
(sensorimotor, kama),
(sensorimotor, moksha) }