This passage is clear and full. Common necessity, or necessity in the original use of the word, refers to the connexion between volition and its effects; for here an opposition to will is supposable. I may choose or will to raise a weight; but the gravity opposed to my endeavour overcomes it, and I find it _impossible_ for me to raise it, and the weight _necessarily_ remains in its place. In this common use of these terms, the _impossibility_ and the _necessity_ are _relative_ to my volition; but in the production of choice itself, or volition, or the sense of the most agreeable, there is no reference to voluntary endeavour. Choice is not the cause of itself: it cannot be conceived of as struggling with itself in its own production. The cause of volition does not lie within the sphere of volition itself; if any opposition, therefore, were made to the production of a volition, it could not be made by a volition. The mind, with given susceptibilities and habits, is supposed to be placed within the influence of objects and their circumstances, and the choice takes place in the correlation of the two, as the sense of the most agreeable. Now choice cannot exist before its cause, and so there can be no choice in the act of its causation. It comes into existence, therefore, by no necessity relating to voluntary endeavour; it comes into existence by a philosophical and absolute necessity of cause and effect. It is necessary as the falling of a stone which is thrown into the air; as the freezing or boiling of water at given temperatures; as sensations of sight, sound, smell, taste, and feeling, when the organs of sense and the objects of sense are brought together. The application of the epithet _moral_ to the necessity of volition, evidently does not alter in the least the character of that necessity. It is still philosophical and absolute necessity, and as sure and perfect as natural necessity. This we have seen he expressly admits, (p. 33;) affirming, (p. 34,) that the difference between a moral and natural necessity is a mere difference in the "two terms connected," and not a difference "_in the nature of the connexion_." _Natural and moral inability._