Laws
A law of Boolean algebra is an equation such as x∨(y∨z) = (x∨y)∨z between two Boolean terms, where a Boolean term is defined as an expression built up from variables and the constants 0 and 1 using the operations ∧, ∨, and ¬. The concept can be extended to terms involving other Boolean operations such as ⊕, →, and ≡, but such extensions are unnecessary for the purposes to which the laws are put. Such purposes include the definition of a Boolean algebra as any model of the Boolean laws, and as a means for deriving new laws from old as in the derivation of x∨(y∧z) = x∨(z∧y) from y∧z = z∧y as treated in the section on axiomatization.
Read more about this topic: Boolean Algebra
Famous quotes containing the word laws:
“Nature and nature’s laws lay hid in the night. God said, Let Newton be! and all was light!”
—Alexander Pope (1688–1744)
“The life of a good man will hardly improve us more than the life of a freebooter, for the inevitable laws appear as plainly in the infringement as in the observance, and our lives are sustained by a nearly equal expense of virtue of some kind. The decaying tree, while yet it lives, demands sun, wind, and rain no less than the green one. It secretes sap and performs the functions of health. If we choose, we may study the alburnum only. The gnarled stump has as tender a bud as the sapling.”
—Henry David Thoreau (1817–1862)
“We agree fully that the mother and unborn child demand special consideration. But so does the soldier and the man maimed in industry. Industrial conditions that are suitable for a stalwart, young, unmarried woman are certainly not equally suitable to the pregnant woman or the mother of young children. Yet “welfare” laws apply to all women alike. Such blanket legislation is as absurd as fixing industrial conditions for men on a basis of their all being wounded soldiers would be.”
—National Woman’s Party, quoted in Everyone Was Brave. As, ch. 8, by William L. O’Neill (1969)