consciousness

The core sense, built plainly from conscious + -ness, and it works in two registers. In everyday talk it is something you have or lose: to lose consciousness after striking one's head. In philosophy and science writing it becomes the puzzle itself. The Economist in 2013 calls the brain's thinking level "presumably, the seat of consciousness," and William Irwin Thompson in 1981 makes it universal, older than the solar system.

Here consciousness has an object. It is knowledge of something, so it reaches for of or a that-clause. The American novelist Winston Churchill's The Celebrity (1897) shows the clause form, with "the consciousness dawning upon him that his eccentricity was not receiving the ovation it merited." That object is how to tell it from the general state of awareness: you lose consciousness, but a consciousness that something is so dawns on you.

Politics uses the word with a modifier that names the cause or group: a feminist consciousness, class consciousness, the "anti-military consciousness" Neil Miller reported in Gay Community News in 1975. The awareness is shared rather than private, which is why a movement can raise it. It often takes the indefinite article, as one consciousness among several.

The count noun that turns a state into a someone: a consciousness is a single aware mind, and it takes the plural consciousnesses. It suits speculative writing about minds that are not human. BioWare's Mass Effect (2007) describes a faith holding that "the universe is a consciousness," with every life within it an aspect of the greater whole.