From: firstname.lastname@example.org (Mr C Smith)
I'd like to butt into the Andy-Davie dispute. (If this sounds familiar, its because I have said it all before.)
If Marx's work means anything, it was as a critique of philosophy as such, where Hegel represented philosophy as such. At the heart of this was the critique of epistemology.
Hegel had already set the ball rolling by introducing philosophy and history to each other. To put it in a smart-arse-philosopher's manner: is epistemology knowledge? Can you have an explanation of explanation? (The best exposition of such questions is in the Introduction [after the Preface] to the Phenomenology. It knocks Kant on the head.) Hegel's answer is in terms of knowledge and truth having a history, showing that they are inseparable from ignorance and falsehood. A philosophical outlook is then seen to be 'its own time expressed in thought'. A 'theory of knowledge' has to be more than a theory, for it must encompass the way of life of the theorist, including that of the philosopher.
Marx goes along with all this, but sees Hegel himself is still only a philosopher, 'the alienated mind of the world', 'thought revolving within itself'. What epistemology assumes is that there are two levels of thinking about thinking: that of the ordinary thinker-in-the-street, and the thinking of the specialist in thought. In other words, its attitude starts out from the division between mental and manual labour, that is, from class society. (Isn't Hegel inconsistent on this? He wants his outlook to be accessible to all the citizens of civil society, but he also accepts the division between shoemakers and philosophers. (See the end of the Preface to the Phenomenology. However, also see his praise for Jakob Boehme, the shoemaker who, Hegel says, founded German philosophy.)
When Andy declares the identity of epistemology and Ethics, I cheered, because I thought he was beginning to recognise this way of seeing things. But he only goes half-way. Hegel also challenged all previous views of Ethics, or at least all modern, ie bourgeois, views. Just as he wants to break down the isolation of knowledge from history, he also wants to distinguish between, and resolve the contradiction between, ethical life and individual morality (Sittlichkeit/Moralitaet). This is crucial to his discussion of Logic, for it bears on the distinction Inner/Outer. (Hegel's Logic comprises will and feeling, don't forget.)
In the end, it all comes down to the way that Hegel studies philosophy and its history. He thinks that philosophy shows the way that modern society can resolve all its contradictions. When the residents of civil society read his books, they will reconcile themselves in the State. Marx knows that the way forward was not a philosophical one at all. The critique of philosophy would lead to revolutionary-critical-practical solutions. That is the crucial meaning of the Theses on Feuerbach, especially 1 and 11.)