Take another instance. Few men, who have studied Gothic spires, have failed to observe that the height of some, in proportion to their base, is too great, and that of others, too small. The mind irresistibly affirms, that between these opposite imperfections, there is a golden mean, at which the proportion shall be _perfect_. When the formula of this proportion shall be studied out, any workman, who is skilled with tools, can construct a perfect spire. The law once discovered and promulgated, becomes common knowledge. Mechanical skill will be all that can differentiate one workman from another. The fact that the law has not been discovered yet, throws no discredit upon the positive affirmation of the mind, that there must be such a law; any more than the fact of Newton's ignorance of the law of gravitation, when he saw the apple fall, discredited his instinctive affirmation, upon seeing that phenomenon, there is a law in accordance with which it fell. Now how comes the mind instinctively and positively to make these assertions. If they were judgments, the mind would only speak of probabilities; but here, it qualifies the assertion with necessity. Men, however positive in their temperament, do not say, "I know it will rain to-morrow," but only, "In all probability it will." Not so here. Here the mind refuses to express itself doubtfully. Its utterance is the extreme of positiveness. It says _must_. And if its affirmation is not true, then there is no _reason_ why those works of art which are held in highest esteem, should be adjudged better than the efforts of the tyro, except the whim of the individual, or the arbitrary determination of their admirers. Fourth. The ideas and beliefs which pertain to morals and religion.