Page:An Enquiry Concerning Human Understanding - Hume (1748).djvu/124

 these Limitations are not known by Reason, or any Contemplation of the Nature of the Cause and the Effect; but only by Experience and Observation, as in all other natural Events and in the Operation of external Objects. Our Authority over our Sentiments and Passions is much weaker than that over our Ideas; and even the latter Authority is circumscrib'd within very narrow Limits. Will any one pretend to assign the ultimate Reason of these Limits, or snow why the Power is deficient in one Case and not in another?

Thirdly, This Self-command is very different at different Times. A Man in Health possesses more of it, than one languishing with Sickness. We are more Masters of our Thoughts in the Morning than in the Evening: Fasting, than after a full Meal. Can we give any Reason for these Variations, except Experience? Where then is the Power, of which we pretend to be conscious? Is there not here some secret Mechanism or Structure of Parts, either in a spiritual or material Substance or both, upon which the Effect depends, and which being altogether unknown to us, renders the Power or Energy of the Will equally unknown and incomprehensible?

is surely an Act of the Mind, with which we are sufficiently acquainted. Reflect upon it.