Abstract: The Gaia theory of James Lovelock proposes that the Earth is a self-regulating system, or super-organism, maintaining conditions hospitable to contemporary planetary biota. Objections to this theory, concerning its alleged untestability and circularity, are considered and countered. Favourable evidence includes Lovelock’s daisyworld model of a planet regulating its own temperatures and thus maintaining homeostasis, and his discoveries of actual regulatory mechanisms such as the biological generation of dimethyl sulphide, which removes sulphur from the oceans and seeds clouds whose albedo reduces solar radiation (a negative feedback mechanism). After some decades of scepticism, sections of the scientific community have partially endorsed Gaia theory, accepting that the Earth system behaves as if self-regulating. Whether or not this theory is acceptable in full, it has drawn attention to the need for preserving planetary biological cycles and for the planetary dimension to be incorporated in ethical decision-making, and thus for a planetary ethic.
Qualia: The Knowledge Argument
Abstract: The knowledge argument aims to establish that conscious experience involves non-physical properties. It rests on the idea that someone who has complete physical knowledge about another conscious being might yet lack knowledge about how it feels to have the experiences of that being. It is one of the most discussed arguments against physicalism.
Personal autonomy
Abstract: To be autonomous is to be a law to oneself; autonomous agents are self-governing agents. Most of us want to be autonomous because we want to be accountable for what we do, and because it seems that if we are not the ones calling the shots, then we cannot be accountable. More importantly, perhaps, the value of autonomy is tied to the value of self-integration. We don’t want to be alien to, or at war with, ourselves; and it seems that when our intentions are not under our own control, we suffer from self-alienation. What conditions must be satisfied in order to ensure that we govern ourselves when we act? Philosophers have offered a wide range of competing answers to this question.
Normative Theories of Rational Choice: Expected Utility
Introduction: This article discusses expected utility theory as a normative theory – that is, a theory of how people should make decisions. In classical economics, expected utility theory is often used as a descriptive theory – that is, a theory of how people do make decisions – or as a predictive theory – that is, a theory that, while it may not accurately model the psychological mechanisms of decision-making, correctly predicts people’s choices. Expected utility theory makes faulty predictions about people’s decisions in many real-life choice situations (see Kahneman & Tversky 1982); however, this does not settle whether people should make decisions on the basis of expected utility considerations. The expected utility of an act is a weighted average of the utilities of each of its possible outcomes, where the utility of an outcome measures the extent to which that outcome is preferred, or preferable, to the alternatives. The utility of each outcome is weighted according to the probability that the act will lead to that outcome. Section 1 fleshes out this basic definition of expected utility in more rigorous terms, and discusses its relationship to choice. Section 2 discusses two types of arguments for expected utility theory: representation theorems, and long-run statistical arguments. Section 3 considers objections to expected utility theory; section 4 discusses its applications in philosophy of religion, economics, ethics, and epistemology.
The Contents of Perception
Summary: In this article, the author provides a great overview on the topic of perceptual content, by addressing the following main issues: i) what are perceptual experiences? ii) what can constitute the content of our experience? iii) what is the relation between the content and our experience? iv) in virtue of what experiences have content?
Wisdom
Introduction: What is wisdom? Philosophers, psychologists, spiritual leaders, poets, novelists, life coaches, and a variety of other important thinkers have tried to understand the concept of wisdom. This entry will provide a brief and general overview, and analysis of, several philosophical views on the topic of wisdom. It is not intended to capture the many interesting and important approaches to wisdom found in other fields of inquiry. Moreover, this entry will focus on several major ideas in the Western philosophical tradition. In particular, it will focus on five general approaches to understanding what it takes to be wise: (1) wisdom as epistemic humility, (2) wisdom as epistemic accuracy, (3) wisdom as knowledge, (4) a hybrid theory of wisdom, and (5) wisdom as rationality.
Gottfried Leibniz: Philosophy of Mind
Abstract: Gottfried Wilhelm Leibniz (1646-1716) was a true polymath: he made substantial contributions to a host of different fields such as mathematics, law, physics, theology, and most subfields of philosophy. Within the philosophy of mind, his chief innovations include his rejection of the Cartesian doctrines that all mental states are conscious and that non-human animals lack souls as well as sensation. Leibniz’s belief that non-rational animals have souls and feelings prompted him to reflect much more thoroughly than many of his predecessors on the mental capacities that distinguish human beings from lower animals. Relatedly, the acknowledgment of unconscious mental representations and motivations enabled Leibniz to provide a far more sophisticated account of human psychology. It also led Leibniz to hold that perception—rather than consciousness, as Cartesians assume—is the distinguishing mark of mentality.
Scientific Realism
Abstract: Debates about scientific realism are closely connected to almost everything else in the philosophy of science, for they concern the very nature of scientific knowledge. Scientific realism is a positive epistemic attitude toward the content of our best theories and models, recommending belief in both observable and unobservable aspects of the world described by the sciences. This epistemic attitude has important metaphysical and semantic dimensions, and these various commitments are contested by a number of rival epistemologies of science, known collectively as forms of scientific antirealism. This article explains what scientific realism is, outlines its main variants, considers the most common arguments for and against the position, and contrasts it with its most important antirealist counterparts.
Classical Logic
Summary: This article provides the basics of a typical logic, sometimes called ‘classical elementary logic’ or ‘classical first-order logic’, in a rigorous yet accessible manner. Section 2 develops a formal language, with a syntax and grammar. Section 3 sets up a deductive system for the language, in the spirit of natural deduction. Section 4 provides a model-theoretic semantics. Section 5 turns to the relationships between the deductive system and the semantics, and in particular, the relationship between derivability and validity. The authors show that an argument is derivable only if it is valid (soundness). Then they establish a converse: that an argument is valid only if it is derivable (completeness). They also briefly indicate other features of the logic, some of which are corollaries to soundness and completeness. The final section, Section 6, is devoted to a brief examination of the philosophical position that classical logic is ‘the one right logic’.
Ancient Logic
Summary: A comprehensive introduction to ancient (western) logic from the 5th century BCE to the 6th century CE, with an emphasis on topics which may be of interest to contemporary logicians. Topics include pre-Aristotelian logic, Aristotelian logic, Peripatetic logic, Stoic Logic and a note on Epicureans and their views on logic.