 Recent critics also disagree with Frege’s and Husserl’s views on the nature of logical laws. In the light of the development of philosophy and logic over the past 70 years, it is no longer evident that the laws of Frege’s and Husserl’s classical logic are necessary and unique. The uniqueness assumption has become more and more questionable as logicians have developed more and more logics (e.g. intuitionist logic, dialethetic paraconsistent and dialectical logic, relevance logic). Not only have Frege and Husserl failed to provide procedures for adjudicating between alternative logics (Baker and Hacker 1989, 88), but it has also turned out that even the Principle of Non-Contradiction which both Frege and Husserl regarded as one of those ‘boundary stones set in an eternal foundation, which our thought can overflow but never displace’, can be violated — without leading to absolute inconsistency. Indeed it is violated in every dialethetic system of logic (Massey 1991, 184).