Then in 1948, a copy of Virtue manuscript found at St. Galen Monastery became the start of theRenaissance Architecturetheories.Leon Bautista Alberti, the person in charge of the constructions commanded by the Pope “On Building” (De re aedifficatoria) will then write the greatest works on the Theory of Architecture. The book was completed in 1452 and published in 1485, with more emphasis on decoration of the building exteriors. Many master builders and thinkers followed then and wrote volumes on the theory of building.Sebastiano Serliowrote the “Regole generall di architectura” canonizing the classical orders.Giacomo Barozzi Vignolawrote the “Regola delle cinque ordini” or the concise facts and easily applicable rules of the five column systems. He based his design instructions on the ideas ofPythagoras, proportions of small number, properties of the material and good taste.Andrea Palladio(1508-1580) wrote “I Quattro libri dell’architectura”. He is known as “The Father of Modern Picture Books of Architecture.”Philibert de L’orme, the French theorist famous for his criticisms of Italians, proved that Pantheon’s Corinthian columns had 3 different proportions. He rejected the doctrine of the absolute beauty of measures.