Consciousness

Philosophy of mind is a branch of philosophy that deals with the nature of the mind and its relation to the body and the external world.

The mind–body problem is a paradigmatic issue in philosophy of mind, although a number of other issues are addressed, such as the hard problem of consciousness and the nature of particular mental states. Aspects of the mind that are studied include mental events, mental functions, mental properties, consciousness and its neural correlates, the ontology of the mind, the nature of cognition and of thought, and the relationship of the mind to the body.

In psychology & philosophy, awareness is the perception or knowledge of something. The concept is often synonymous with consciousness; however, one can be aware of something without being explicitly conscious of it (e.g., blindsight).

The states of awareness are also associated with the states of experience, so that the structure represented in awareness is mirrored in the structure of experience.

A coma is a deep state of prolonged unconsciousness in which a person cannot be awakened, fails to respond normally to painful stimuli, light, or sound, lacks a normal sleep-wake cycle and does not initiate voluntary actions. The person may experience respiratory and circulatory problems due to the body's inability to maintain normal bodily functions. People in a coma often require extensive medical care to maintain their health and prevent complications such as pneumonia or blood clots. Coma patients exhibit a complete absence of wakefulness and are unable to consciously feel, speak or move. Comas can be the result of natural causes, or can be medically induced, for example, during general anesthesia.

Clinically, a coma can be defined as the consistent inability to follow a one-step command. For a patient to maintain consciousness, the components of wakefulness and awareness must be maintained. Wakefulness is a quantitative assessment of the degree of consciousness, whereas awareness is a qualitative assessment of the functions mediated by the cerebral cortex, including cognitive abilities such as attention, sensory perception, explicit memory, language, the execution of tasks, temporal and spatial orientation and reality judgment. Neurologically, consciousness is maintained by the activation of the cerebral cortex—the gray matter that forms the brain's outermost layer—and by the reticular activating system (RAS), a structure in the brainstem.

The mind is that which thinks, feels, perceives, imagines, remembers, and wills. It covers the totality of mental phenomena, including both conscious processes, through which an individual is aware of external and internal circumstances, and unconscious processes, which can influence an individual without intention or awareness. The mind plays a central role in most aspects of human life, but its exact nature is disputed. Some characterizations focus on internal aspects, saying that the mind transforms information and is not directly accessible to outside observers. Others stress its relation to outward conduct, understanding mental phenomena as dispositions to engage in observable behavior.

The mind–body problem is the challenge of explaining the relation between matter and mind. Traditionally, mind and matter were often thought of as distinct substances that could exist independently from one another. The dominant philosophical position since the 20th century has been physicalism, which says that everything is material, meaning that minds are certain aspects or features of some material objects. The evolutionary history of the mind is tied to the development of nervous systems, which led to the formation of brains. As brains became more complex, the number and capacity of mental functions increased with particular brain areas dedicated to specific mental functions. Individual human minds also develop over time as they learn from experience and pass through psychological stages in the process of aging. Some people are affected by mental disorders, in which certain mental capacities do not function as they should.

Reason is the capacity of consciously applying logic by drawing valid conclusions from new or existing information, with the aim of seeking truth. It is associated with such characteristically human activities as philosophy, religion, science, language, and mathematics, and is normally considered to be a distinguishing ability possessed by humans. Reason is sometimes referred to as rationality, although the latter is more about its application.

Reasoning involves using more-or-less rational processes of thinking and cognition to extrapolate from one's existing knowledge to generate new knowledge, and involves the use of one's intellect. The field of logic studies the ways in which humans can use formal reasoning to produce logically valid arguments and true conclusions. Reasoning may be subdivided into forms of logical reasoning, such as deductive reasoning, inductive reasoning, and abductive reasoning.

Property dualism describes a category of positions in the philosophy of mind which hold that, although the world is composed of just one kind of substance—the physical kind—there exist two distinct kinds of properties: physical properties and mental properties. In other words, it is the view that at least some non-physical, mental properties (such as thoughts, imagination and memories) exist in, or naturally supervene upon, certain physical substances (namely brains).

Substance dualism, on the other hand, is the view that there exist in the universe two fundamentally different kinds of substance: physical (matter) and non-physical (mind or consciousness), and subsequently also two kinds of properties which inhere in those respective substances. Both substance and property dualism are opposed to reductive physicalism. Notable proponents of property dualism include David Chalmers, Christof Koch, and Richard Fumerton. It became prominent in the final decades of the twentieth century and is now the leading alternative to physicalism.

In epistemology (theory of knowledge), a self-evident proposition is a proposition that is known to be true by understanding its meaning without proof, and/or by ordinary human reason.

Some epistemologists deny that any proposition can be self-evident. For most others, one's belief that oneself is conscious and possesses free will are offered as examples of self-evidence. However, one's belief that someone else is conscious or has free will are not epistemically self-evident.

The meaning of life is the concept of an individual's life, human life, or existence in general having an inherent significance or a philosophical point. There is no consensus on the specifics of such a concept, or whether the concept itself even exists in any objective sense. Thinking and discourse on the topic is sought in the English language through questions such as—but not limited to—"What is the meaning of life?", "What is the purpose of existence?", and "Why are we here?". There have been many proposed answers to these questions from many different cultural and ideological backgrounds. The search for life's meaning has produced much philosophical, scientific, theological, and metaphysical speculation throughout history. Different people and cultures believe different things for the answer to this question. Opinions vary on the usefulness of using time and resources in the pursuit of an answer. Excessive pondering can be indicative of, or lead to, an existential crisis.

The meaning of life can be derived from philosophical and religious contemplation of, and scientific inquiries about, existence, social ties, consciousness, and happiness. Many other issues are also involved, such as symbolic meaning, ontology, value, purpose, ethics, good and evil, free will, the existence of one or multiple gods, conceptions of God, the soul, and the afterlife. Scientific contributions focus primarily on describing related empirical facts about the universe, exploring the context and parameters concerning the "how" of life. Science also studies and can provide recommendations for the pursuit of well-being and a related conception of morality. An alternative, humanistic approach poses the question, "What is the meaning of my life?"

Mental substance, according to the idea held by dualists and idealists, is a non-physical substance of which minds are composed. This substance is often referred to as consciousness.

This is opposed to the view of materialists, who hold that what we normally think of as mental substance is ultimately physical matter (i.e., brains).