to act, it would cease to be; and that cessation of thought is but another name for extinction of mind. This argument is subtile, but not conclusive; because it supposes what cannot be proved, that the nature of mind is properly defined. Others affect to disdain subtilty, when subtilty will not serve their purpose, and appeal to daily experience. We spend many hours, they say, in sleep, without the least remembrance of any thoughts which then passed in our minds; and since we can only by our own consciousness be sure that we think, why should we imagine that we have had thought of which no consciousness remains?
This argument, which appeals to experience, may from experience be confuted. We every day do something which we forget when it is done, and know to have been done only by consequence. The waking hours are not denied to have been passed in thought; yet he that shall endeavour to recollect on one day the ideas of the former, will only turn the eye of reflection upon vacancy; he will find, that the greater part is irrevocably vanished, and wonder how the moments could come and go, and leave so little behind them.