[Note: In this post when I refer to Smith I mean John Smith, not Adam Smith.]
Smith and value
Unlike Lenin’s “Imperialism: The Highest Stage of Capitalism” and Baran and Sweezy’s “Monopoly Capital,” Smith in his “Imperialism” has set himself the task of explaining the imperialist—monopolist—phase of capitalism in terms of Marx’s theory of value and surplus value. Smith has set himself the extremely ambitious task of unifying Marx’s “Capital” with Lenin’s 1916 pamphlet. In addition, he seeks to update the Leninist theory of imperialism for the early 21st century. The logical starting point of such an ambitious undertaking is the theory of value.
John Smith, Keynes and left Keynesians on value
“The exchange-value of a commodity,” Smith writes on p. 58 of his “Imperialism,” is determined not by the subjective desires of the buyers and sellers, as both orthodox and heterodox economic theory maintains, but by how much effort it took to make it.” Smith makes an important point here. Both orthodox economists (the so-called neoclassical school and the Austrian school) and heterodox economists (left Keynesians) support or at least do not challenge the marginalist theory of value, which for more the century has dominated academic economic orthodoxy.
The marginalist theory of value holds that value arises from the scarcity of useful objects, which may be products of either human labor or nature, relative to subjective human needs. Instead of beginning with production and labor, as both the classical school and Marx did, marginalists begin with the subjective valuations of the consumer.
A Critique of Crisis Theory 
A brief comment on your take on Left Keynesians at the beginning of your otherwise very useful (and enjoyable) piece. In Cambridge (UK) in 1970s, a whole slew of them rejected marginalist theory. Joan Robinson, in fact, frequently ridiculed it, in spite of Keynes´s chapter in the General Theory.
Hi Sam
about rent, again….
a few quotes from Vol III
From Chapter 40
Let us first consider just the formation of surplus-profit with differential rent II, without for the present bothering about the conditions under which the transformation of this surplus-profit into ground-rent may take place.
It is then evident that differential rent II is merely differently expressed differential rent I, but identical to it in substance. The variation in fertility of various soil types exerts its influence in the case of differential rent I only in so far as unequal results are attained by capitals invested in the soil, i.e., the amount of products obtained either with respect to equal magnitudes of capital, or proportionate amounts. Whether this inequality takes place for various capitals invested successively in the same land or for capitals invested in several plots of differing soil type — this can change nothing in the difference in fertility nor in its product and can therefore change nothing in the formation of differential rent for the more productively invested portions of capital. It is still the soil which, now as before, shows different fertility with the same investment of capital, save that here the same soil performs for a capital successively invested in different portions what various kinds of soil do in the case of differential rent I for different equal portions of social capital invested in them.
From Chapter 39
We shall first consider the unequal results of equal quantities of capital applied to different plots of land of equal size; or, in the case of unequal size, results calculated on the basis of equal areas.
The two general causes of these unequal results — quite independent of capital — are: 1) Fertility. (With reference to this first point, it will be necessary to discuss what is meant by natural fertility of land and what factors are involved.) 2) The location of the land. This is a decisive factor in the case of colonies and in general determines the sequence in which plots of land can be cultivated. Furthermore, it is evident that these two different causes of differential rent — fertility and location — may work in opposite directions. A certain plot of land may be very favourably located and yet be very poor in fertility, and vice versa. This circumstance is important, for it explains how it is possible that bringing into cultivation the land of a certain country may equally well proceed from the better to the worse land as vice versa. Finally, it is clear that the progress of social production in general has, on the one hand, the effect of evening out differences arising from location as a cause of ground-rent, by creating local markets and improving locations by establishing communication and transportation facilities; on the other hand, it increases the differences in individual locations of plots of land by separating agriculture from manufacturing and forming large centres of production, on the one hand, while relatively isolating agricultural districts, on the other.
For the present, however, we shall leave this point concerning location out of consideration and confine ourselves to natural fertility. Aside from climatic factors, etc., the difference in natural fertility depends on the chemical composition of the top soil, that is, on its different plant nutrition content. However, assuming the chemical composition and natural fertility in this respect to be the same for two plots of land, the actual effective fertility differs depending on whether these elements of plant nutrition are in a form which may be more or less easily assimilated and immediately utilised for nourishing the crops. Hence, it will depend partly upon chemical and partly upon mechanical developments in agriculture to what extent the same natural fertility may be made available on plots of land of similar natural fertility. Fertility, although an objective property of the soil, always implies an economic relation, a relation to the existing chemical and mechanical level of development in agriculture, and, therefore, changes with this level of development.
From Chapter 45
[…}the mere existence of an excess in the value of agricultural products over their price of production would not in itself suffice to explain the existence of a ground-rent which is independent of differences in fertility [and we may argue that , passim, fertility means fertility + location] of various soil types and in successive investments of capital on the same land — a rent, in short, which is to be clearly distinguished in concept from differential rent and which we may therefore call absolute rent.