Content without method ends in sentimental chaos;
Method without content in sophistry;
Material without form is a dead-weight of fact;
Form without material is a spinning of cobwebs.(Johann Wolfgang von Goethe, Theory of Color, 1810)
"The principal subject of our study is economic equilibrium. We shall see shortly that this equilibrium results from the opposition between men's tastes and the obstacles to satisfying them. Our study includes, then, three distinct parts: 1ｰ the study of tastes; 2ｰ the study of obstacles; 3ｰ the study of the way in which these two elements combine to reach equilibrium."
(Vilfredo Pareto, Manual of Political Economy, 1906: p.106)
"Walras is in my opinion the greatest of all economists. His system of economic equilibrium, uniting, as it does, the quality of a "revolutionary" creativeness with the quality of classic synthesis, is the only work by an economist that will stand comparison with the achievements of theoretical physics. Compared with it, most of the theoretical writings of that period - and beyond - however valuable in themselves and however original subjectively, look like boats beside a liner, like inadequate attempts to catch some particular aspects of Walrasian truth."
(J. A. Schumpeter, History of Economic Analysis, 1954: p.827)
"My propositions are elucidatory in this way: he who understands me finally recognizes them as senseless, when he has climbed out through them, on them, over them. (He must so to speak throw away the ladder, after he has climbed up on it.)
He must surmount these propositions; then he sees the world rightly."
(Ludwig Wittgenstein, Tractatus Logico-Philosophicus, 1921: Prop. 6.54)