Since the very beginnings of economics as a science, which might be dated from Ibn Khalduns Introduction to History (1377), the challenge of making societies escape from poverty and attain some degree of prosperity has always been, and will remain, a fundamental issue. It was and it is still...

The Slutsky equation can be constructed as a parallelogram (a diamond), the area of which is proportional to the elasticity of substitution. This construction permits to show immediately that demand functions become concave on an interval if the elasticity of substitution increases sufficiently....