When asked why he never wrote a book, John ('Rabbi') Duncan (1796-1870) replied, 'I cannot write, I'm just a talker.' Duncan had a genius for expressing profound thoughts in brief epigrammatic sayings. 'What I have sought to do in these pages is take the aphorisms of his conversations, as recorded in several original sources and present them here in one book, believing that they will greatly enrich the hearts and minds of all who read them. The amount of clear thought packed into these pages is altogether out of proportion to their number. Duncan's sayings have a near unique combination of depth and brevity. He exemplified the standard he expected of other: 'I would advise everyone to be very careful to use no more words than are necessary to express thought. Whenever a man becomes cloudy in his words, be sure that his thought has become shadowy too.' On Duncan's death, William Knight remarked, 'With him has perished a breathing library of wisdom.'