Marshall and Walras: Incompatible Bedfellows?

The standard view about the relation between the Marshallian and the Walrasian approaches is that they are complementary to each other. My aim in this paper is to show that, on the contrary, they constitute alternative sub-research programs within the wider neoclassical paradigm. I make my point by contrasting the two approaches against the following benchmarks: the purpose of economic theory according to Marshall and Walras, their views as to the role of mathematics, their ways of looking at the working of the economy as whole, the conception of equilibrium underpinning their theories and, finally, their trade organization assumptions