The evolution of mind is the most fundamental feature of the human kingdom, and it is hoped that human mind will become more enlightened, more united with beauty, compassion, and wisdom. It is the human mind that makes cultures. We live in a most remarkable episode of history, where the thought heritage of many cultures is coming together. Deep wisdom has been written in these books, as far as wisdom can be written down, and there are many hints which can help the unbiased reader to evolve inner, higher intuitive faculties, which in turn help him understand much more than might at first appear from the dead letter of the books. These works can be fully understood if we have the keys, but the keys must be sought.
Material knowledge leads to accumulation of facts and imperfect transitory theories.
Spiritual knowledge leads to wisdom. Wisdom leads to recognition of the inherent oneness and inseparability of all life, and therefore to recognition of the brotherhood of all being. Recognition of brotherhood evokes compassion, and compassion is the most beneficent power for the betterment and well-being of all nature. For this reason, it would be beneficial if the studies of ecology were extended to learning what non-Western cultures have to say about nature, life, and attitudes towards living beings. Many great teachers have stated that the higher powers of nature are compassionate and helpful.