Logic

• Aristotle came up with logic 2500 years ago, and we still use it.
• He used it to analyze arguments, to show if they were valid.
• Prolog, is programming in logic.
• Statements have truth values, true or false. This is a real simplification of reality, but we all understand it.
• Statements are connected with and, exclusive or, inclusive or, not, if and equivalence.
• You can use logic tables to decide if connected statements are true.
• So, if A is true, and B is true, then A and B is true. If one (or both) is false, A and B is false.
• See logic tables for the full set.
• You can also use functions. So taller(Bob,X) makes X the set of things that Bob is taller than.
• A lot of AI works with these simple logics, but there are more complex non-monotonic logics, and higher order logics.