There are still other viewpoints that see continued interaction between member countries as an adequate guarantor of tax stability. Specifically, it can be argued that interactions within the EU framework (specifically with respect to the Stability and Growth Pact) protect against harmful tax competition, therefore rendering superfluous any additional tax harmonization rules. Thierry Warin and André Fourçans, who use a game theoretical approach to predict the outcome of the European tax situation, adopt this logic. As is true for almost all the literature reviewed, there exists the belief that some degree of tax competition does in fact exist, and demands a response. Yet the paper questions the EU's harmonization strategy, where taxes on savings will face "a minimum common rate of 15% until 2004, then 20% until the end of 2009 " (Fourçans, 3) The main reason is this: "as monetary policy is 'federalized', and as fiscal policy is constrained by the Stability and Growth Pact, taxation becomes the last macroeconomic instrument within governments' hands to deal with asymmetric shocks." (Fourçans, 4) With this in mind, tax harmonization appears overly restrictive. Yet the argument goes further by demonstrating that even a minimum tax floor may be unnecessary. Using game theory between member countries, it is argued that infinite interactions prevents a race to the bottom, and "underlines the role of tax competition to reach stability of the system." (Fourçans, 5) This stability is undeniably enhanced by each country's adherence to the Stability and Growth Pact: In the game theory model provided, "it is of a paramount importance for a country to be able to give a strong signal to the other country that a war of attrition is possible. For that, countries must have sound public finances." (Fourçans, 17) Clearly, the Stability and Growth Pact assures the existence of such sound public finances.