"Another source of the sublime is infinity... Infinity has a tendency to fill the mind with that sort of delightful horror, which is the most genuine effect and truest test of the sublime. There are scarce any things which can become the objects of our senses, that are really... infinite. But the eye not being able to perceive the bounds... they seem... infinite, and they produce the same effects... We are deceived in the like manner, if the parts of some large object are so continued to any indefinite number, that the imagination meets no check... Whenever we repeat an idea frequently, the mind... repeats it long after the first cause has ceased... multiplied without end. ...This is the reason of an appearance very frequent in madmen; that they remain... in the constant repetition of some remark... complaint, or song... every repetition reinforces it with new strength... unrestrained by the curb of reason, continues... to the end of their lives."