The definition and classification of polycystic ovary syndrome (PCOS) have been an important but controversial topic for many decades with significant implications for treatment and prognosis. The 2018 international guideline incorporates evidence-based evaluation of the condition together with clinical, consumer, academic and industry contributions to set up the most accepted approach to diagnosis, evaluation and treatment available internationally.

Galen insists that genuine epistêmê, in the Aristotelian sense of securely-founded scientific understanding, is available to the serious medical investigator. The foundations consist in propositions that are evidently true, and hence require no further support. These come in two types: those evident to the senses and those evident to reason, and these are ex heautôn pista, self-crediting, intrinsically trustworthy. On the basis of such propositions the diligent inquirer can erect a firmly-founded structure of practical knowledge, a technê, but one which is, none the less, in a genuine sense demonstration. In this chapter I re-examine what Galen says about a number of inter-related key issues: What is the ‘orderly method’ of discovery which Galen regularly commends, and berates his opponents for failing to adhere to? What supplies the ‘context of justification’ for such a firmly-founded science, and how does this relate to Galen’s oft-repeated affirmation of the necessity for empirical testing, peira? And finally, and relatedly, what specific role in all of this is played by what he calls ‘differentiated experience’, peira diorismenê?

In Chapter 7, I argued that it was appropriate for us to ascribe understanding to young children and computers, as their behavior meets the criteria of correctness and intersubjectivity. What they cannot yet do, I argued, is ascribe understanding – that is, claim or attribute understanding – to themselves or others. Why does that matter?

In this chapter I argue that Aristotle is seeking, in the De Anima, to explain why it is in human nature to know beings (all beings). The argument rests in part on how Aristotle introduces his agenda and in part on a criticism he makes of his predecessors. I also discuss various qualifications that must be made to that introduction and that criticism in order to bring them in line with Aristotle’s considered views.

Chapter 1 examines war’s place in a universal paradigm of order and chaos, balance and imbalance; explores war’s origins and relationship to human nature; and concludes by formally defining war. After relating Aristotle’s “four causes” model (material, formal, efficient, and final) to war as an organizing concept, the chapter articulates war’s alignment within a universal theme of balance and characterizes war as an amalgam of twenty “dialectics,” including order-chaos and creation-destruction. It highlights how political imbalances can spark war and how dialectical disparities undermine war theory and strategy. Next, the chapter marshals multidisciplinary evidence to argue that evolutionary processes have imbued humanity with warlike and peaceful attributes and that war ultimately reflects human choices arising from various motives including Thucydides’s fear, honor, and interest. Finally, the chapter concludes by defining war as the nexus of a new trinity – humanity, politics, and combat – evaluating the boundaries between war and peace, and taking a first look at the question of war’s inevitability as a human activity.

This chapter challenges the binary contrast between ’myth’ and rational account (logos), reviewing the negative impact of the application of that dichotomy when used to draw contrasts between properly scientific modes of discourse and those to be dismissed as irrational. Ethnographic reports show that there is often no equivalent to our term ’myth’ in indigenous vocabularies, at least not one that carries similar pejorative undertones. The arguments of Lévi-Strauss that systems of myth may convey ’concrete science’ have the merit of taking those systems seriously, but still imply a pejorative binary judgement.

This chapter examines the varying roles that definitions may play in scientific investigations. Obviously they may laudably aim at clarifying the problem to be explored, but the demand and search for univocal definitions can have a limiting effect on the inquiry subsequently pursued. When a definition is presented as the goal of an investigation, for example of the characteristics of an animal species, that may have the effect of obscuring some of the complexities that may be uncovered along the way. The problem of the role of definitions in an axiomatic system such as Euclid’s lies in their presumed self-evidence.

This chapter studies Locke’s critique of scholastic language, but since this “learned gibberish” is, for Locke, only one form of insignificant speech, the chapter then proceeds to discuss his views about the requirements for significant speech and the remedies proposed in case these requirements are not met. Locke’s answer contains elements that, at first sight, cannot be reconciled with each other so easily: his linguistic thesis according to which words as arbitrary signs are imposed by the mind on its ideas has a mentalistic and even solipsistic ring to it, yet communication is a social activity, governed by rules, customs, and conventions. The chapter therefore ends by looking in more detail at the social dimension of language to see how the social world shapes our apparently private minds. It concludes that for Locke the mind is a social entity, embedded in social and linguistic practices that shape our views of the world and give expression to them. The social world is built on the ideas we receive and construct, and common linguistic usage, for all its imperfections, is essential in framing and conveying these ideas.

This chapter studies Hobbes’s use of common language not only in his attacks on the “insignificant speech” of the scholastics but also in the definitions of his own philosophy. Thomas Hobbes was a careful observer of linguistic usage, appealing often to “what we are used to say.” But he does not accept “common usage” in any simple way. Like so many of his contemporaries, Hobbes was ambivalent about common language. As a move in his polemical invectives against scholastic language, Hobbes chose the side of “the people” who used language in a “natural” and “common” way. But common language also reflected patterns of thinking that Hobbes found deeply disturbing. Since for Hobbes everything hinges on the right understanding of words and well-explained definitions, he often claims to have common language at his side, yet we also find him subtly redefining terms to match his own philosophical views. The chapter explores Hobbes’s balancing act of revising ordinary language while playing down the revising act itself. In the last section the chapter suggests that the revision of common usage is part of Hobbes’s wider tactic to persuade the people that his civil science comes close to what every reasonable person should endorse.

The idea there is a “balance of nature” was a staple of the schools of natural philosophy from which biology emerged. Not until the second half of the twentieth century was the concept of a balance of nature rigorously characterized as ecological stability, and the metaphysical speculations about its cause superseded with scientific hypotheses about its basis. But significant uncertainty and controversy exists about what features of an ecological system’s dynamics should be considered its stability and thus no consensus has emerged about how ecological stability should be defined. Instead, ecologists have employed a confusing multitude of different terms to attempt to capture apparent stability properties, e.g., constancy, persistence, resilience, resistance, robustness, tolerance. This chapter diagnoses and resolves the underlying lack of conceptual clarity about ecological stability. It presents a comprehensive account of stability as a three-fold concept that crucially depends on two reference specifications. The account clarifies the concepts ecologists have used that are defensible, their interrelationships, and their potential relationships with other biological properties. Besides providing insights about how problematic scientific concepts should be characterized, the idea that ecological stability is a conceptually confused concept is also criticized.

This chapter describes the biodiversity concept and guides the reader through the growing scientifically oriented philosophical literature on biodiversity. Although the concept’s significance is common currency within environmental ethics, biodiversity has only recently garnered broader philosophical attention. Whatever the correct account of the structure and dynamics of biological communities, some are clearly more complicated than others. For example, tropical communities usually contain more species, there is evidence their species interact more intensely, these interactions are more variegated in form, and they exhibit more trophic levels than high latitude communities. Coined as a simple shorthand for “biological diversity,” “biodiversity” captures this notion of ecological diversity and much more, including developmental, morphological, and taxonomic diversity. How biodiversity should be characterized thus depends on how these systems are represented, particularly on how their parts are individuated, classified, and distributed among those classes. Several adequacy conditions on characterizing this diversity are proposed, and value-driven attempts to define the concept are criticized. It also makes the first connection, explored in later chapters, between ecology proper and the kind of applied ecology conducted in efforts to conserve biodiversity.

In this chapter, the influence of Hellenistic philosophy on Roman law is discussed in terms of method: with the help of the Stoic dialectical methods of classifying and defining the Roman jurists could start to systematise the organically grown output of their civil law and turn the resolution of disputes into a scientific enterprise, producing systematic overviews along the way. In the 6th century CE, the Roman Emperor Justinian took the influential decision that an updated version of one of these accounts itself be given the status of law.

It is now a cliché to observe that, despite innumerable efforts to define terrorism, scholars are no nearer to arriving at a consensus. One approach has been to assemble the multitude of definitions produced by academics, commentators, governments and international organisations, in an attempt to identify common ground. There is much to admire in this ethos of catholicity – though the final product can feel more like a catalogue of component parts than a cohesive and workable definition. How, then, should historians approach the debate over how to define terrorism? To explore this question, this chapter begins by reflecting on the ‘genealogical turn’ in historical method – a development closely associated with the ‘Cambridge school’ of intellectual history. It will then attempt to construct a genealogy for ‘terrorism’, as reflected in existing historical narratives of this subject. And finally, it will consider what key themes emerge from such a genealogical examination.

Chapter 1 summarizes the main concepts representing the pillars of trait-based ecology. Key definitions from the literature, and widely used in the book, are synthetized and clarified. This includes an in-depth discussion of which traits are to be considered more functional, dissecting the relationship between species traits and species fitness and how this can change across different habitats. The classic distinction between response and effect traits is introduced, together with some broad open challenges for future research in trait-based ecology.

This chapter frames the complex and contested concept of Christian Platonism explicated throughout this volume. Here, it is introduced as an object of theological and philosophical contention, the subject of historical and conceptual communication, and a theme of compulsory knowledge for the student of intellectual history.

This chapter is an overall introduction to the definition of pattern recognition, its relationship with machine learning and other relevant subject areas, and the main components and development process inside a pattern recognition system. This introduction is started by considering an autonomous driving example.