The Genesis of Computers

The Genesis of Computers: From Aristotle to Shannon

• Aristotle wrote The Organon, a six-part book on human reasoning that became the beginning of what we today refer to as logic.
• Aristotle's biggest observation was that you can tell whether an argument is valid or not merely by looking at its structure.
• Aristotle also defined other basic principles of logic in The Organon that would be influential, such as no statement can be both true and false.
• In 1854, George Boole attempted to improve logic by taking Aristotle's logic and represent it using symbols, operators, and variables.
• Boole's book, The Laws of Thought, turned logic into a science similar to Geometry or Calculus.
• Boole created a new notation for logic that helped scholars and thinkers to devise long equations or logical “proofs” for all sorts of concepts and ideas.
• In 1938, Claude Shannon realized that the rules of logic as described by Aristotle and Boole could be represented in an electrical circuit.
• Shannon's thesis, titled “A Symbolic Analysis of Switching and Relay Circuits”, described something revolutionary that would become the basis for arithmetical logic units or ALUs—an essential element of a computer’s CPU.
• The true and false circuits developed by Shannon could be combined together to make mathematical operations like addition or subtraction.
• The Von Neumann Architecture and the invention of the transistor would develop this technology into what we know as computers today.
• At its core, the computer is a representation of Aristotle’s rules of logic rendered in digital electrical circuits.
• The computer's origin story began with Aristotle's fascination with the ways in which the human mind works and his observation that you can tell whether an argument is valid or not merely by looking at its structure.