The term revolution is normally used to indicate a sharp change in the direction of evolution of a given phenomenon, a catastrophe, in the jargon of modern dynamic theory. In this sense we often talk of the Newtonian revolution in physics or of a Neoclassical revolution in economics.

Alfred Marshall, who once proclaimed that the Mecca of the economist lies in Economic Biology, is remembered more for the mechanical analogies contained in the appendices of his Principles of Economics. Subsequent revisions of Marshall based on the mechanical principles he incorporated into the theory of the firm (Robbins 1928; Pigou 1928), the theory of competition (Robinson 1933; Chamberlin 1933), and the theory of value (Hicks and Allen 1934), succeeded in completely removing the corpus of economic theory from the domain of biology.

Alfred Marshalls monetary theory presents itself as fragmentary and without internal coherence. Coherence can be given to it by developing the implied theoretical linkages between the money market, the securities market, and their respective interest rates, while noting the importance in interest- rate determination of the real forces of productivity and thrift.Marshalls development of a theory of money and securities markets arises from his dissatisfaction with the quantity theory of price-level determination as an explanation of the monetary transmission mechanism

Adam Smiths adding up theory (Sraffa 1951, p. xxxv) has generally been interpreted as an expression of the harmonious view of the mechanisms governing exchange ratios and distribution In two preceding works (Nistico 1988,1991) I tried to show that Smith's theory of prices is instead fully compatible with the classical approach to the theory of value and distribution based on the essential role played by class antagonism in a capitalist system.

David Ricardo was a peaceful man, well liked and admired for both his intellectual and his personal traits by his colleagues and rivals whether on the Stock Exchange, in the nascent field of political economy, or among the members of Parliament. He could maintain personal friendship and wellbehaved exchange of ideas with someone as far removed from him in both religion and economic doctrine as Thomas Malthus. The intellectual strength of his written work could dominate the thought of such a great mind as that of John Stuart Mill and rouse the writer Thomas de Quincey from his opiumriddled state to renewed mental vigor.

The resurgence of neo-Schumpeterian theories and models of technological innovation and development1 is an enduring sign of the historical significance of Joseph A. Schumpeters theoretical works on the dynamics of economic change as a result of long-term technological change.

Henry George has many admirers, but only a few scholarly economists would regard him as one of their own. In this paper, I wish to argue not only that Henry George made a sound contribution to political economy; I also claim that his analysis is eminently significant for environmental economics today.

Hans Karl Emil von Mangoldt (1824-1868) is often cited as making an important contribution to German economic theory in his major work, Grundriss der Volkswirtschaftslehre (1863), which was written as a text for further discussion in classes. Yet the details of his compressed analysis have rarely been given close attention.