Let 0 and 1 denote the null and unit elements of a Boolean algebra B. The following four functions with argument in B and values in B are of fundamental importance in Boolean algebra. They are: the null function, defined by 0x = 0; the unit function, defined by 1x = 1; the identity function j, defined by jx = x, and the complementary function c, defined by the rule, ex is the complement of x. These four functions, 0, 1, j, c, form a tri-operational algebra in the sense of Karl Menger.
Proceedings of the Iowa Academy of Science
© Copyright 1946 by the Iowa Academy of Science, Inc.
Chittenden, E. W.
"On the Characterization of the Algebra of Four Fundamental Boolean Functions,"
Proceedings of the Iowa Academy of Science, 53(1), 247-248.
Available at: https://scholarworks.uni.edu/pias/vol53/iss1/29