 Hartley had a warrant for this affirmative approach to languages in his scientific and mathematical training: Newton wrote the Principia in the language of geometry, but the “mathematical principles of natural philosophy” could be equally (and better?) expressed in the “algebraic” language of the calculus—for which there were rival notations. Similarly, Hartley championed a new “notation” for the English language—his friend John Byrom’s shorthand, which he saw as a reform that would make our written language more closely approximate a “philosophical” one. When he began work on the Observations, he conceived of the project as demonstrating that language about “self-interest,” the “common good,” and the “will of God” were different ways of saying the same thing. The project was thus as much moral and religious as it was scientific.