Why is the economic model better for policy than the biological model alone?

Economic policies claim to describe policies that will improve peoples’ lives. This is unlike the biological one that has a policy component, however for the most part they are concerned with understanding the functioning of their respective subject matter. Biological policy, of course, has the potential to improve peoples’ standards of living, but it is really a by-product of science as an intellectual activity. Many methodologists have missed this essential feature of economic science. It is a mistake to compare economics to Biology. None of these is concerned with policy making and is much concerned about methodology. There is no model of methodology for a policy science on which we can build an analysis. The task of constructing such a theory falls to economists

Economic policy would lead to an objective function. For example, if economics are making choices to maximize something, then we can get an idea of what is being optimized by looking at their choices. This objective function can then be used as an input for policy decisions. In some cases, one may need a quantitative estimate of the objective function. In other cases, one may want to show that one kind of market structure, may do a better job of satisfying consumers objectives than other, which is not possible with a biological policy outlook.