“French philosopher and scientist, Rene Descartes said, ‘Cogito, ergo sum — I think, therefore I am.’ He was correct.
Consciousness may involve thoughts, sensations, perceptions, moods, emotions, dreams, and self-awareness. It is variously seen as a type of mental state, a way of perceiving, or a relationship between self and other. It has been described as a point of view, an I, or what Thomas Nagel called the existence of ‘something that it is like’ to be something.
Many philosophers have seen consciousness as the most important thing in the universe. On the other hand, many scientists have seen the word as too nebulous in meaning to be useful.
Consciousness is the subject of much research in philosophy of mind, psychology, neuroscience, cognitive science, and artificial intelligence. Issues of practical concern include how the presence of consciousness can be assessed in severely ill or comatose people; whether non-human consciousness exists and if so how it can be measured; at what point in fetal development consciousness begins; and whether computers can achieve conscious states.
In common parlance, consciousness sometimes also denotes being awake and responsive to the environment, in contrast to being asleep or in a coma.
Consciousness is a term that refers to the relationship between the mind and the world with which it interacts. It has been defined as: subjectivity, awareness, the ability to experience or to feel, wakefulness, having a sense of selfhood, and the executive control system of the mind.
Despite the difficulty in definition, many philosophers believe that there is a broadly shared underlying intuition about what consciousness is. As Max Velmans and Susan Schneider wrote in The Blackwell Companion to Consciousness: ‘Anything that we are aware of at a given moment forms part of our consciousness, making conscious experience at once the most familiar and most mysterious aspect of our lives.’ ”
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