Kepler's law vs law of nature

Kepler's law and law of nature both are nouns.

Word	Noun	Adjective	Verb	Adverb
Kepler's law	Yes	No	No	No
law of nature	Yes	No	No	No

As nouns, law of nature is a hypernym of Kepler's law; that is, law of nature is a word with a broader meaning than Kepler's law:

Kepler's law: (astronomy) one of three empirical laws of planetary motion stated by Johannes Kepler
law of nature: a generalization that describes recurring facts or events in nature

Other hypernyms of Kepler's law include law.

Kepler's law (noun)	law of nature (noun)
(astronomy) one of three empirical laws of planetary motion stated by Johannes Kepler	a generalization that describes recurring facts or events in nature