Under many and diverse names and veils, the doctrine of Rebirths has been taught from the farthest antiquity right up to the present time. There is not a nation that has not preserved clear traces of this doctrine; not a religion that has not taught it, either openly or in secret, or, at all events, retained the germ of the teaching; and if we count only those peoples of whose national religion it forms part, i.e., Hindus and Buddhists, the number of believers in Reincarnation may be summed up in round figures at 540 millions of the present population of 1400 millions throughout the world (in 1910 when this book was first published). The greatest of philosophers, both ancient and modern, have regarded palingenesis as the basis of life, but whereas in the past the pledge of initiation prevented its details from being promulgated, in our days, along with the flood of light which this cycle has brought us, the veil of secrecy has been partially lifted, and theosophy has been privileged to set forth this glorious teaching in its main outlines and its most important details.