noun
natural philosophy
Historical term for the philosophical study of nature, especially before the development of modern science. Often used in the context of early modern European thought.
ニュートンは自然哲学の数学的諸原理を著した。
Newton wrote the Mathematical Principles of Natural Philosophy.
自然科学 refers to modern natural science, while 自然哲学 is the historical philosophical precursor.
Compound of 自然 (nature) and 哲学 (philosophy), likely a calque from Western languages such as English 'natural philosophy' or Latin 'philosophia naturalis'.