Introduction

• Consciousness and our experience of self and world are central puzzles in understanding the mind.

• There is no universally agreed theory of consciousness, but consensus holds that understanding consciousness and its relation to nonconscious reality is essential.

• Questions about conscious awareness have existed as long as humans, with early evidence from Neolithic burial practices indicating some reflective thought on consciousness.

• Preliterate cultures often held spiritual or animist views implying reflection on conscious awareness.

• Some scholars argue consciousness as known today is a recent historical development, emerging after the Homeric era (Jaynes 1974).

• Ancient Greeks lacked a specific word corresponding to modern “consciousness,” though they discussed mental matters.

• The Reformation emphasis on conscience as an inner source of truth influenced the modern reflective view of self.

• By the early modern era (17th century), consciousness became central to theories of mind.

• René Descartes defined thought (pensée) as all that we are conscious of operating within us (1640).

• John Locke emphasized consciousness as essential to thought and personal identity but refrained from theorizing its substance or relation to matter (1688).

• G.W. Leibniz proposed a mind theory with infinitely many degrees of consciousness, introducing the distinction between perception (awareness) and apperception (self-awareness) and argued consciousness cannot arise from mere matter (Monadology, 1720).

• For two centuries, thought and consciousness were mostly equated, with associationist psychology (Locke, Hume, James Mill, John Stuart Mill) focusing on how conscious ideas interact.

• John Stuart Mill introduced early ideas of mental emergence, where combinations of ideas produce novel results beyond their parts (1865).

• Immanuel Kant critiqued associationism, arguing that phenomenal consciousness requires a structured mental organization and a conscious self situated in space, time, and causality (1787).

• In Europe, phenomenology developed through Husserl, Heidegger, Merleau-Ponty, expanding study of consciousness into social, bodily, and interpersonal realms (early 20th century).

• Early scientific psychology equated mind with consciousness, using introspection (Wundt, Helmholtz, James, Titchener).

• The relation between consciousness and brain remained mysterious (Huxley, 1866).

• Behaviorism in early 20th-century U.S. largely rejected consciousness as a scientific subject (Watson, Skinner), though Gestalt psychology in Europe maintained interest.

• The 1960s cognitive psychology revived focus on internal mental processes but largely neglected consciousness.

• In the 1980s-90s, consciousness research resurged in science and philosophy, marked by key works (Baars, Dennett, Penrose, Crick, Lycan, Chalmers).

• This resurgence led to new journals (Journal of Consciousness Studies, Consciousness and Cognition, Psyche), societies (ASSC), and dedicated conferences (“The Science of Consciousness”).

Concepts of Consciousness

• The terms “conscious” and “consciousness” are umbrella terms encompassing a wide variety of mental phenomena.

• Both terms have a diversity of meanings depending on context.

• The adjective “conscious” is heterogeneous in meaning.

• It can be applied to whole organisms (referred to as creature consciousness).

• It can also be applied to particular mental states and processes (referred to as state consciousness).

Creature Consciousness

• An animal, person, or cognitive system may be regarded as conscious in several different senses.

• Sentience refers to being conscious in a generic sense as a sentient creature capable of sensing and responding to its environment (Armstrong 1981).

• Sentience may admit of degrees, and the exact sensory capacities required are not sharply defined; examples include questioning if fish, shrimp, or bees qualify as conscious in this sense.

• Wakefulness requires not just the ability but the actual exercise of sensory capacity, meaning the organism must be awake and alert to be considered conscious.

• Organisms are not conscious when asleep or in deep coma; borderline cases include dreaming, hypnosis, or fugue states where consciousness is unclear.

• Self-consciousness is a more demanding sense of consciousness, involving awareness of being aware (Carruthers 2000).

• Self-awareness may be interpreted in various ways, with some requiring explicit conceptual self-awareness (possibly excluding many non-human animals and young children), and others accepting rudimentary implicit self-awareness which would include more nonlinguistic creatures.

• Thomas Nagel’s (1974) “what it is like” criterion captures a subjective notion of consciousness, meaning there is something it is like to be that creature from its own experiential point of view.

• Nagel’s example of bats illustrates that although humans may not understand the bat’s experience, the bat is conscious because there is a unique subjective experience associated with its echo-locatory senses.

• Conscious organisms can be defined in terms of having conscious mental states, where the definition depends on how one defines conscious states themselves (section 2.2 referenced).

• There is a distinction between intransitive consciousness (being conscious generally) and transitive consciousness, where consciousness is directed at or of some object (Rosenthal 1986).