Before the 18th century, Discrete, quantity and space astronomy, physics Example: planetary orbital, Newton's Laws in Three Dimensions continuous mathematics: calculus Equations of Mathematical Physics, Functions of Real Variable, Functions of complex variable Discrete stagnancyBefore the 18th century, Discrete， quantity and space astronomy, physics Example: planetary orbital, Newton's Laws in Three Dimensions continuous mathematics: calculus, Equations of Mathematical Physics, Functions of Real Variable,Functions of complex Variable Discrete ? stagnancy