scientifically, there is not perhaps, at the present moment, so general an agreement as would be desirable to give effect to their conclusions; and the writers who peculiarly call themselves practical, either draw no general inferences, or are so much influenced by narrow, partial, and sometimes interested views, that no reliance can be placed on them for the establishment of general rules. The last twenty or thirty years have besides been marked by a train of events of a most extraordinary kind; and there has hardly yet been time so to arrange and examine them as to see to what extent they confirm or invalidate the received principles of the science to which they relate.
The present period, therefore, seems to be unpropitious to the publication of a new systematic treatise on political economy. The treatise which we already possess is still of the very highest value; and till a more general agreement shall be found to take place, both with respect to the controverted points of Adam Smith's work, and the nature and extent of the additions to it, which the more advanced stage of the science has rendered necessary, it is obviously more advisable that the different subjects which admit of doubt should be treated separately. When these discussions have been for some time before the public, and a sufficient opportunity has been given, by the collision of different opinions and an appeal to experience, to separate what is true from what is false, the different parts may then be combined into a consistent whole, and may be expected to carry with it such weight and authority as to produce the most useful practical results.
The principal cause of error, and of the differences which prevail at present among the scientific writers on political economy, appears to me to be a precipitate attempt to simplify and generalize. While their more practical opponents draw too hasty inferences from a frequent appeal to partial facts, these writers run into a contrary extreme, and do not sufficiently try their theories by a reference to that enlarged and
