Boolean algebra is the most powerful tool in the expert searcher's toolbox.
Boolean algebra is embedded in the human psychology, in the very biochemical wiring of the human brain itself. It is the foundation of all of mathematics, and most of philosophy. Boolean algebra is used throughout the search examples in the following pages. Hotbot Infoseek - Advanced Yahoo Operators and Operands. Boolean algebra is like any algebra, consisting of expressions made up of a combination of operators and operands.