Consciousness is simply the light by which the contours of mind and body are known. It is that which is aware of feelings such as joy, regret, amusement, and despair. It can seem to take their shape for a time, but it is possible to recognize that it never quite does. In fact, we can directly experience that consciousness is never improved or harmed by what it knows. Making this discovery, again and again, is the basis of spiritual life.

Consciousness is a being the nature of which is to be conscious of the nothingness of its being.

Consciousness is the awareness that emerges out of the dialectical tension between possibilities and limitations.

Consciousness is the basis of both the examined and the unexamined life. It is all that can be seen and that which does the seeing. No matter how far you have traveled from the place of your birth, and however much you now understand about the world, you have been exploring consciousness and its changes. Why not do so directly?

I will argue that consciousness is not a thing. “Consciousness” is the word we use to describe the subjective feeling of a number of instincts and/or memories playing out in time in an organism. That is why “consciousness” is a proxy word for how a complex living organism operates. And, to understand how complex organisms work, we need to know how brains’ parts are organized to deliver conscious experience as we know it.

Chalmers: It’s awfully hard to define consciousness. But I’d start by saying that it’s the subjective experience of the mind and the world. It’s basically what it feels like, from the first-person point of view, to be thinking and perceiving and judging.

Consciousness is the one thing in the universe that cannot be an illusion — even if I'm a brain in a vat, all my memories are false, and my perceptions are of a world that doesn't exist, I'm still having an experience.

In brief: consciousness is a phenomenon in the zone of evolution. This world lights up to itself only where or only inasmuch as it develops, procreates new forms. Places of stagnancy slip from consciousness; they may only appear in their interplay with places of evolution.
If this is granted it follows that consciousness and discord with one's own self are inseparably linked up, even that they must, as it were, be proportional to each other. This sounds a paradox, but the wisest of all times and peoples have testified to confirm it. Men and women for whom this world was lit in an unusually light of awareness, and who by life and word have, more than others, formed and transformed that work of art which we call humanity, testify by speech and writing or even by their lives that more than others have they been torn by the pangs of inner discord. Let this be a consolation to him who also suffers from it. Without it nothing enduring has ever been begotten.

Consciousness is the basis of both the examined and the unexamined life.

I think that consciousness is the way information feels when being processed in certain complex ways.

Consciousness is a born hermit.

Consciousness is a singular of which the plural is unknown; … there is only one thing and that, what seems to be a plurality, is merely a series of different aspects of this one thing, produced by a deception (the Indian MAYA); the same illusion is produced in a gallery of mirrors …

Consciousness of unconsciousness

Consciousness is the one thing in this universe that cannot be an illusion