 Berlin further asserted that values may be not only incompatible, but incommensurable. There has been considerable controversy over what he meant by this, and whether his understanding of incommensurability was either correct or coherent. In speaking of the incommensurability of values, Berlin seems to have meant that there is no common measure, no ‘common currency’ in terms of which the relative importance of any two values can be established in the abstract. Thus one basic implication of pluralism for ethics is the view that a quantitative approach to ethical questions (such as that envisaged by Utilitarianism) is impossible. In addition to denying the existence of a common currency for comparison, or a governing principle (such as the utility principle), value incommensurability holds that there is no general procedure for resolving value conflicts – there is not, for example, a lexical priority rule (that is, no value always has priority over another).