In the 16th edition of Science and Health Mrs. Eddy quotes from a sermon by William Ellery Channing: “The philosopher has often been led to question whether anything really exists in the universe, beyond Mind and Spirit; whether matter and the body have any substantial being; whether apparently external nature be not an actual creation of our own growth; or, in other words, whether, in believing in an outward world, we do anything more than ascribe reality to our own conceptions.”