Some important things have been given Professor Hurwicz's name such as the Hurwicz criterion, an idea that Professor Hurwicz had in 1950, and is thought of as very important for economics. The Hurwicz Criterion is also called "under uncertainty". Hurwicz had the idea of putting Abraham Walds work together with work done by Pierre-Simon Laplace in 1812. The Hurwicz Criterion tells people to think very carefully of what is good and what is bad before making decisions. Different types of the Hurwicz Criterion have been thought of. Leonard Jimmie Savage made some changes to the first Hurwiczs criterion in 1954. The four peoples work – Laplace, Wald, Hurwicz and Savage – that the Hurwicz Criterion has been based on was studied, corrected and used for over fifty years by many different people including John Milnor, G. L. S. Shackle, Daniel Ellsberg, R. Duncan Luce and Howard Raiffa, but some people say the work was started by Jacob Bernoulli.