To study the symbolism of Masonry is the only way to investigate its philosophy. This is the portal of its temple, through which alone we can gain access to the sacellum where its aporrheta are concealed. Its philosophy is engaged in the consideration of propositions relating to God and man, to the present and the future life. Its science is the symbolism by which these propositions are presented to the mind. The work now offered to the public is an effort to develop and explain this philosophy and science. It will show that there are in Freemasonry the germs of profound speculation. If it does not interest the learned, it may instruct the ignorant. If so, I shall not regret the labor and research that have been bestowed upon its composition. Albert G. Mackey, M.D. Charleston, S.C., Feb. 22, 1869