Thought experimentA thought experiment is a hypothetical situation in which a hypothesis, theory, or principle is laid out for the purpose of thinking through its consequences. The ancient Greek deiknymi, "was the most ancient pattern of mathematical proof", and existed before Euclidean mathematics, where the emphasis was on the conceptual, rather than on the experimental part of a thought-experiment. Johann Witt-Hansen established that Hans Christian Ørsted was the first to use the term Gedankenexperiment (from German: 'thought experiment') circa 1812.
SentienceSentience is the ability to experience feelings and sensations. The word was first coined by philosophers in the 1630s for the concept of an ability to feel, derived from Latin sentiens (feeling), to distinguish it from the ability to think (reason). In modern Western philosophy, sentience is the ability to experience sensations. In different Asian religions, the word "sentience" has been used to translate a variety of concepts. In science fiction, the word "sentience" is sometimes used interchangeably with "sapience", "self-awareness", or "consciousness".
Hard problem of consciousnessThe hard problem of consciousness is a philosophical problem concerning why and how humans and other organisms have qualia, phenomenal consciousness, or subjective experiences. This is in contrast to the "easy problems" of explaining the physical systems that give humans and other animals the ability to discriminate, integrate information, perform behavioural functions, or provide behavioural reports, and so forth.
Mind–body dualismIn the philosophy of mind, mind–body dualism denotes either the view that mental phenomena are non-physical, or that the mind and body are distinct and separable. Thus, it encompasses a set of views about the relationship between mind and matter, as well as between subject and object, and is contrasted with other positions, such as physicalism and enactivism, in the mind–body problem.
Functionalism (philosophy of mind)In philosophy of mind, functionalism is the thesis that each and every mental state (for example, the state of having a belief, of having a desire, or of being in pain) is constituted solely by its functional role, which means its causal relation to other mental states, sensory inputs, and behavioral outputs. Functionalism developed largely as an alternative to the identity theory of mind and behaviorism. Functionalism is a theoretical level between the physical implementation and behavioral output.
SolipsismSolipsism (ˈsɒlᵻpsɪzəm; ) is the philosophical idea that only one's mind is sure to exist. As an epistemological position, solipsism holds that knowledge of anything outside one's own mind is unsure; the external world and other minds cannot be known and might not exist outside the mind. There are varying degrees of solipsism that parallel the varying degrees of skepticism: Metaphysical solipsism Metaphysical solipsism is a variety of solipsism.
PanpsychismIn the philosophy of mind, panpsychism (pænˈsaɪkɪzəm) is the view that the mind or a mindlike aspect is a fundamental and ubiquitous feature of reality. It is also described as a theory that "the mind is a fundamental feature of the world which exists throughout the universe." It is one of the oldest philosophical theories, and has been ascribed to philosophers including Thales, Plato, Spinoza, Leibniz, William James, Alfred North Whitehead, Bertrand Russell, and Galen Strawson.
EpiphenomenalismEpiphenomenalism is a position on the mind–body problem which holds that physical and biochemical events within the human body (sense organs, neural impulses, and muscle contractions, for example) are the sole cause of mental events (thought, consciousness, and cognition). According to this view, subjective mental events are completely dependent for their existence on corresponding physical and biochemical events within the human body, yet themselves have no influence over physical events.
Inverted spectrumThe inverted spectrum is the hypothetical concept, pertaining to the philosophy of color, of two people sharing their color vocabulary and discriminations, although the colors one sees—one's qualia—are systematically different from the colors the other person sees. The concept dates back to John Locke. It invites us to imagine that we wake up one morning, and find that for some unknown reason all the colors in the world have been inverted, i.e. swapped to the hue on the opposite side of a color wheel, the complementary color.
Possible worldA possible world is a complete and consistent way the world is or could have been. Possible worlds are widely used as a formal device in logic, philosophy, and linguistics in order to provide a semantics for intensional and modal logic. Their metaphysical status has been a subject of controversy in philosophy, with modal realists such as David Lewis arguing that they are literally existing alternate realities, and others such as Robert Stalnaker arguing that they are not.