Synchronicity: An Acausal Connecting Principle. (From Vol. 8. of the Collected Works of C. G. Jung) (New in Paper) (Bollingen Series XX: the Collected Works of C. G. Jung, Volume 8)

It is generally believed that numbers were invented or thought out by man, and therefore nothing but concepts of quantities, containing nothing that was not previously put into them by human intellect. But it is equally possible that numbers were found or discovered. Pg. 41