The same idea, when it again recurs without the operation of the like object on the external sensory, is if it be sought after by the mind, and with pain and endeavour found, and brought again in view, it is if it be held there long under attentive consideration, it is when ideas float in our mind without any reflection or regard of the understanding, it is that which the French call our language has scarce a name for it: when the ideas that offer themselves (for, as I have observed in another place, whilst we are awake, there will always be a train of ideas succeeding one another in our minds) are taken notice of, and, as it were, registered in the memory, it is when the mind with great earnestness, and of choice, fixes its view on any idea, considers it on all sides, and will not be called off by the ordinary solicitation of other ideas, it is that we call or sleep, without dreaming,