Britannica says;
Society of Friends, Christian group that arose in mid-17th-century England, dedicated to living in accordance with the "Inner Light," or direct inward apprehension of God, without creeds, clergy, or other ecclesiastical forms. As most powerfully expressed by George Fox (1624-91), Friends felt that their "experimental" discovery of God would lead to the purification of all of Christendom. It did not. But Friends founded one American colony and were dominant for a time in several others, and, though their numbers are now comparatively small, they have made disproportionate contributions to science, industry, and especially to the Christian effort for social reform.
From the website "Britannica"
Tom Wolfe's (Author of this book) notes: "Britannica" may say the Society of Friends did not "purify Christianity". However each heart that has experimental discovery of God speaks for itself. "33 Ways 7 Faiths Agree with the Quakers" shows God's faithful consistency over thousands of years showing 33 common Principles of 8 of the world's Faiths that learn us how to as we Quakers say: "Let Our Lives Speak"