together (incohere). If two elements p and q cohere they are connected by a positive constraint , and if two elements and incohere they are connected by a negative constraint . Furthermore, constraints are weighted, i.e., for each constraint there is a positive weight . According to Thagard, coherence maximization involves the partitioning of elements into accepted () and rejected () elements in such a way that maximum number (or maximum weight) of constraints is satisfied. Here a positive constraint is said to be satisfied if either both and are accepted () or both and are rejected (). A negative constraint is satisfied if one element is accepted (say ), and the other rejected (). Philosophy of science There has been some decrease in interest in the demarcation problem in recent years. Part of the problem is that many suspect that it is an intractable problem, since so many previous attempts have come up short. For example, many obvious examples of pseudoscience have been shown to be falsifiable, or verifiable, or revisable. Therefore, many of the previously proposed demarcation criteria have not been judged as particularly reliable. Thagard has proposed another set of principles to try to overcome these difficulties. According to Thagard's method, a theory is not scientific if: He describes the Aristotelian realist philosophy of mathematics as "the current philosophy of mathematics that fits best with what is known about minds and science." Major works Thagard is the author/co-author of 13 books and over 200 articles. Brain-Mind: From Neurons to Consciousness and Creativity. (Oxford University Press, 2019). Mind-Society: From Brains to Social Sciences and Professions. (Oxford University Press, 2019). The Cognitive Science of Science: Explanation, Discovery, and Conceptual Change. (MIT Press, 2012). The Brain and the Meaning of Life Princeton University Press, 2010 Hot Thought: Mechanisms and Applications of Emotional Cognition (MIT Press, August, 2006, ) Coherence in Thought and Action (MIT Press, 2000, ) How Scientists Explain Disease (Princeton University Press, 1999, ) Mind: An Introduction to Cognitive Science (MIT Press, 1996; second edition, 2005, )(Trad. esp.: La mente, Buenos Aires/Madrid, Katz editores S.A, 2008, ) Conceptual Revolutions (Princeton University Press, 1992, ) Computational Philosophy of Science (MIT Press, 1988, Bradford Books, 1993, ) And co-author of: Mental Leaps: Analogy in Creative Thought (MIT Press, 1995, ) Induction: Processes of Inference, Learning, and Discovery (MIT Press, 1986, Bradford Books, 1989, ) He is also editor of: Philosophy