What difference does difference make?

Agriculture does not develop according to the pattern traced by industry: it follows its own laws. Of this there can be no doubt. . . . This does not mean that the development of agriculture and industry are opposed and irreconcilable. As long as they are regarded as common elements in one overall process, and not existing in mutual isolation, both can be shown to be advancing toward the same end. . . . An investigation of the agrarian question which purports to follow Marx's method cannot simply focus on the question as to whether the smallholder has a future. Rather it has to consider all the changes through which agriculture has passed over the course of the capitalist mode or production: whether, and how, capital is seizing hold of agriculture, revolutionizing it, making old forms of production and property untenable and creating the necessity for new ones. . . . Once we have answered these questions, we can then proceed to see whether Marx's theory is applicable to agriculture or not.