数学原理 shùxuéyuánlǐ mathematical principles Origin Definitions Defs Strokes Stroke Words Sentences Sents 自然哲学之数学原理 zìránzhéxuézhīshùxuéyuánlǐ Philosophiæ Naturalis Principia Mathematica the foundational work by Isaac Newton, published in 1687, laying out the laws of motion and universal gravitation