The age of esotericism has come to an end and the age of open teaching is upon us. The hierophants of ancient Egypt were very cunning in the methods they adopted to hide their knowledge and even invented two kinds of symbolic alphabets, the hieroglyphic and the hieratic, for the use of themselves, their students, and initiated members of the aristocracy, leaving the common demotic alphabet for the use of the masses. The Brahmins of India severely punished any one among them who revealed their teachings to the multitude. Most of the lama masters of Tibet made candidates for instruction undergo a long probation before the higher teachings were communicated to them. The necessity of reserve was strongly impressed upon his followers by Pythagoras, so that his own and their writings are involved in obscurity, covered with symbolism, and often misleading if taken literally. But times have changed since those ancient days. Brahmin writers have revealed their own religious system to the world. The ashrams of great Yogis publish, in books accessible to all who can read, the sayings and teachings of the Yogi masters. The Tibetan adepts sent Blavatsky to the West to disseminate a part of their teaching through Theosophy. From these and other instances it should be clear that the old policy of secrecy has been abandoned. There are not only intellectual reasons for this change in policy--such as the general diffusion of learning and literacy as masses who could not formerly read or write are everywhere acquiring or have acquired these abilities--but also a much more important one: humanity itself is faced with such a tremendous peril that the peril of divulging the divine mysteries is small by comparison. The discovery of atomic power has placed in its hands a weapon with which it threatens to destroy itself, to eradicate its society, and to eliminate its civilization from the face of this planet. In these tragic and unprecedented circumstances, it is a duty laid upon philosophy to come to the help of those individuals, however few, who are sufficiently impressed by the gravity of their situation, whether before or after the great destruction has taken place, to seek for the true sources of life, guidance, strength, and grace as their only refuge, their only salvation.
-- Notebooks Category 20: What Is Philosophy? > Chapter 2: Its Contemporary Influence > # 3