All these discoveries were brought together in that immortal work, Newton's "Principia."
Descartes' Principia and his Meditationes were written in Latin.
When Newton heard of it he began the Principia, working in silence.
It was by this continuous application that the Principia was accomplished.
No sooner was the Principia put than Hooke put in his claims for priority.
All these deductions are fundamental, and may be considered as the foundation of the Principia.
This is published in the Principia as a fact, without comment.
It was only in the second edition of the Principia that the theory of comets was introduced.
You know that Newton said it cost him more labour than all the rest of the Principia.
Descartes wrote a work with this title, Principia Philosophi.