_Less attractive Aspects._--"In this picture of our emotions, however, I have presented them in their fairest aspects; there are aspects which they assume, as terrible as these are attractive; but even terrible as they are, they are not the less interesting objects of our contemplation. They are the enemies with which our mortal combat, in the warfare of life, is to be carried on; and of these enemies that are to assail us, it is good for us to know all the arms and all the arts with which we are to be assailed; as it is good for us to know all the misery which would await our defeat, as well as all the happiness which would crown our success, that our conflict may be the stronger, and our victory, therefore, the more sure. "In the list of our emotions of this formidable class, is to be found every passion which can render life guilty and miserable; a single hour of which, if that hour be an hour of uncontrolled dominion, may destroy happiness forever, and leave little more of virtue than is necessary for giving all its horror to remorse. There are feelings as blasting to every desire of good that may still linger in the heart of the frail victim who is not yet wholly corrupted, as those poisonous gales of the desert, which not merely lift in whirlwinds the sands that have often been tossed before, but wither even the few fresh leaves, which on some spot of scanty verdure, have still been flourishing amid the general sterility." _Difficulty of the Study._--With regard to the difficulty attending the study of this part of our nature, a word seems necessary in passing. It has been supposed to constitute a peculiar difficulty in the way of the successful investigation of this department of mental activity, that the sensibilities are, in their very nature, of such an exciting character, as to preclude the calm, dispassionate observation and reflection so necessary to correct judgment. At the moment of exercising any lively emotion, as hope, fear, anger, etc., the mind is in too great perturbation to be in any condition for accurate self-observation, and when the excitement has subsided, the important moment has already passed. Mr. Stewart has particularly noticed this difficulty in his Introduction to the Active and Moral Powers, and quotes Hume to the same effect.