A Mathematical Logician By: Hanan Mohammed George John Boole (1815-1864) Objectives: Who is this guy? Why should we know him? Impact on Mathematical and Logical fields Who is George John Boole ? Sun of shoes a seller and a lady maid John interest in mathematics Start going to school Interests in education? Eldest sibling,…so? Who is George BooleA student & A teacher Finance obstacles and educational Became teacher assistant to support family Serious mathematics learning start! Establish his own school Published in Cambridge Mathematical Journal Duncan Gregory, editor Who is George BooleA Star Mathematician Queens College Mathematics professor First Mathematics professor Science department Dean Several calculus accomplishments Applied algebra to solve differential equations Who is George BooleBoolean algebra maker Algebra of logic: Boolean algebra Regarded Logic as aspect of Mathematics Mathematical Analysis of Logic Discovered analogy between algebraic symbols and logic forms An Investigation of the Laws of Thought (1854), on Which are Founded the Mathematical Theories of Logic and Probabilities Why do we care Represent Logic as mathematical formulas • Manipulated as normal algebraic expressions • Value of input and output is: true/false • Horned and sheep example (=x & y) Why do we care Boolean Algebra Rules • P1: X = 0 or X = 1 • P2: 0 . 0 = 0 • P3: 1 + 1 = 1 • P4: 0 + 0 = 0 • P5: 1 . 1 = 1 • P6: 1 . 0 = 0 . 1 = 0 • P7: 1 + 0 = 0 + 1 = 1 Why do we care Boolean Algebra Laws • Idempotent Law – X+X=X – X X=X • Involution Law – 0’=1 – 1’=0 – (X’)’=X • Complementarily Law – X+X’=1 – X X’=0 Why do we care Boolean Algebra Laws • Associative Law – (X+Y)+Z = X+(Y+Z) = X+Y+Z – (X Y) Z = X (Y Z) = X Z Y • Distributive Law – X (Y+Z) = X Y+X Z – X+(Y Z) = (X+Y) (A+Z) • Commutative Law – X+Y=Y+X – X Y=X Y Why do we care Boole's work is the basis of mechanisms Claude Shannon after 70 years extends Boole's studies Design system electromechanics through Boolean algebra Solved Boolean Algebra through circuits