His book is rich in statistical observations，and is particularly instructive on the economic effects of different geographicalconditions.It is well adapted for the teaching of public servants whose duties are connected with economics，and it was infact the source from which the German official world down to the seventies of the 19th century derived its knowledge of thescience.In his earlier period Rau had insisted on the necessity of a reform of economic doctrine (Ansichten derVolkswirthschaft ，1821)，and had tended towards relativity and the historical method；but he afterwards conceived themistaken notion that that method "only looked into the past without studying the means of improving the present，"andbecame himself purely practical in the narrower sense of that word.He has the merit of having given a separate treatment of Unternehmergewinn ，or"wages of management."Nebenius，minister in Baden，who was largely instrumental in thefoundation of the Zollverein，was author of a highly esteemed monograph on public credit (1820).The Staatswirthschafthiche Untersuchungen (1832；2d ed.，1870)of Hermann do not form a regular system，but treat a series ofimportant special subjects.His rare technological knowledge gave him a great advantage in dealing with some economicquestions.He reviewed the principal fundamental ideas of the science with great thoroughness and acuteness."His strength，"says Roscher，"lies in his clear，sharp，exhaustive distinction between the several elements of a complex conception，or theseveral steps comprehended in a complex act."For keen analytical power his German brethren compare him with Ricardo.
But he avoids several one-sided views of the English economist.Thus he places public spirit beside egoism as an economicmotor，regards price as not measured by labour only but as a product of several factors，and habitually contemplates theconsumption of the labourer，not as a part of the cost of production to the capitalist，but as the main practical end ofeconomics.Thünen is known principally by his remarkable work entitled Der Isolirte Staat in Beziehung aufLandwirthschaft und National?konomie (1826；3d ed.，1875).In this treatise，which is a classic in the political economy ofagriculture，there is a rare union of exact observation with creative imagination.With a view to exhibit the naturaldevelopment of agriculture，he imagines a state，isolated from the rest of the world，circular in form and of uniform fertility，without navigable rivers or canals，with a single large city at its centre，which supplies it with manufactures and receives inexchange for them its food-products，and proceeds to study the effect of distance from this central market on the agriculturaleconomy of the several concentric spaces which compose the territory.The method，it will be seen，is highly abstract，but，though it may not be fruitful，it is quite legitimate.The author is under no illusion blinding him to the unreality of thehypothetic case.The supposition is necessary，in his view，in order to separate and consider apart one essentialconditionthat，namely，of situation with respect to the market.It was his intention (imperfectly realised，however)toinstitute afterwards several different hypotheses in relation to his isolated state，for the purpose of similarly studying otherconditions which in real life are found in combination or conflict.The objection to this method lies in the difficulty of thereturn from the abstract study to the actual facts；and this is probably an insuperable one in regard to most of itsapplications.The investigation，however，leads to trustworthy conclusions as to the conditions of the succession of differentsystems of land economy.The book abounds in calculations relating to agricultural expenditure and income，which diminishits interest to the general reader，though they are considered valuable to the specialist.They embody the results of thepractical experience of the author on his estate of Tellow in Mecklenburg-Schwerin.Thünen was strongly impressed withthe danger of a violent conflict between the middle class and the proletariate，and studied earnestly the question of wages，which he was one of the first to regard habitually，not merely as the price of the commodity labour，but as the means ofsubsistence of the mass of the community.He arrived by mathematical reasonings of some complexity at a formula whichexpresses the amount of "natural wages"as =where a is the necessary expenditure of the labourer for subsistence，andp is the product of his labour.To this formula he attributed so much importance that he directed it to be engraved on histomb.It implies that wages ought to rise with the amount of the product；and this conclusion led him to establish on hisestate a system of participation by the labourers in the profits of farming，of which some account will be found in Mr.SedleyTaylor's Profit-sharing between Capital and Labour (1884).Thünen deserves more attention than he has received inEngland；both as a man and as a writer he was eminently interesting and original；and there is much in Der Isolirte Staat andhis other works that is awakening and suggestive.
