Notes: Kenneth J. Arrow (95), the Nobel-winning economist and mathematician, has recently passed away at Palo Alto in California, United States. To date, he is the youngest person ever to have received Nobel Prize for Economics, at the age of 51. His theories on risk, innovation and the basic mathematics of markets have influenced thinking on everything from voting to health insurance to high finance. His most significant works are his contributions to social choice theory, Arrow’s impossibility theorem and general equilibrium analysis. He has also provided foundational work in many other areas of economics, including endogenous growth theory and the economics of information.