The ideas of the economists aren't abstract categories, but rather real historical permutations. There are general aspects to production, but they are very tied to the historical moment. The Method of Political Economy pp. The method of rising from the abstract to the concrete is only the way in which thought appropriates the concrete, reproduces it as the concrete in the mind. This is the way the mind apprehends reality, but not the way reality is produced itself.
Reality exists outside the thoughts of people.
Move from the simple relations, such as division of labor, labor to the level of the state, exchange between nations and the world market. This is the proper methodological path. The more simple the abstraction the more developed the concrete category. Labor is an abstract category, but it represents many different forms. Only when in reality a category is more complex does abstraction become possible.