"… the best way to understand a group is to
see it as the group of symmetries of something."

— John Baez, p. 239, Bulletin (New Series) of the
American Mathematical Society , Vol. 42, No. 2,
April 2005, book review on pp. 229–243
electronically published on January 26, 2005

"Imagine yourself as a gem cutter,
turning around this diamond…."

— Ibid ., p. 240

See also related material from Log24.