My refutation of VAR does not mean that I am against quantitative risk management-having spent most of my adult life as a quantitative trader, I learned the hard way the pitfalls of such methods. I am simply against the application of unseasoned quantitative methods. I think that VAR would be a wonderful measurement if financial models were designed for that purpose and if we knew something about their parameters. The validity of VAR is linked to the problem of probabilistic measurement of future events, particularly those deemed infrequent (more than two standard deviations) and those that concern multiple securities. I conjecture that the methods we currently use to measure such tail probabilities are flawed.