Another of the most powerful ways in which scientific discovery has promoted moral progress has been an indirect one, viz., by diminishing ignorance. Deficiency of knowledge is the parent of a vast {133} amount of evil and failure. "There is no instance on record of an active ignorant man, who, having good intentions, and supreme power to enforce them, has not done far more evil than good." (Buckle, "History of Civilization," vol. 1, p. 167). Ignorance largely precludes happiness, and intelligence is an indispensable condition of the highest morality. There are plenty of difficult positions in life in which the desire to do right is not alone sufficient, we must intelligently know what is the right course to pursue. We are all of us ignorant in different degrees, and must be content in many matters to walk by faith until we can walk by sight, and to act according to rule and precept until we have discovered general principles to guide us:--blind dogmatic morality and "rule of thumb" method is vastly better than none, and has rendered great services to mankind. Whether comforting doctrines are true or not, the great bulk of mankind prefer them because they afford immediate relief; and whether they be erroneous or truthful, men will be benefited by them and continue to believe in them, until their minds are sufficiently advanced to receive a knowledge of verified principles. Rules of morality however, when presented to us with a basis of demonstrable truth, come with a degree of divine authority, and possess greater claim to our observance, than the same rules presented to us as empirical or dogmatic statements only.