We do not have to wait for future discoveries in connection with the powers of the human mind for evidence that the mind is the greatest force known to mankind. We know, now, that any idea, aim or purpose that is fixed in the mind and held there with a will to achieve or attain its physical or material equivalent, puts into motion powers that cannot be conquered.
Napoleon Hill (1960). “The Law of Success in Sixteen Lessons: Teaching, for the First Time in the History of the World, the True Philosophy Upon which All Personal Success is Built”