Date: 1971, 1979

"Thinking is trying to better one's instructions; it is trying out promissory tracks which will exist, if they ever do exist, only after one has stumbled exploringly over ground where they are not."

— Ryle, Gilbert (1900-1976)

Date: 1996

"One would expect, then, that such a political period would be rife with various veins of pseudo-mysticism, enamoured of whatever gives the slip to the concept, enthralled by those spasms of mind which confound its customary distinctions, which breed in us some ecstatic state of indeterminacy in ...

— Eagleton, Terry (b. 1943)

Date: 1999

"As the brain gets more complex in the womb, then, like a dimmer switch, consciousness gradually grows and burgeons until, of course, in adulthood it reaches its particular pinnacles or depths."

— Greenfield, Susan (b. 1950)

Date: 1999

"On its own this trigger, as we can see from the earlier definition, is not going to generate consciousness. Imagine a candyfloss machine with a stick in the centre that then gathers more and more candyfloss as time goes on. Think of the epicentre as the stick in the centre, the burgeoning candy...

— Greenfield, Susan (b. 1950)

Date: 1999

"Another rather simplistic analogy might be a boss, at the centre of a big organization that is eventually going to recruit managers and submanagers. What in the brain could be the equivalent of the boss? The most obvious candidate, and one that might immediately spring to mind, is the basic comp...

— Greenfield, Susan (b. 1950)

Date: 1999

"Perhaps the consciousness of dreaming is the almost random formation of little groups forming in different configurations like pebbles thrown very gently into the water. One can imagine the gentle ripples easily being displaced by the next pebble as it hits the water."

— Greenfield, Susan (b. 1950)

Date: 2006

"In power mindfulness, the mind is like a megawatt searchlight, enabling you to see so much deeper into what you are gazing at."

— Ajahn Brahm [born Peter Betts] (August 7, 1951)

Date: 2006

"When there is no longer any wobble, then the mind is like an unwavering rock, more immovable than a mountain and harder than a diamond."

— Ajahn Brahm [born Peter Betts] (August 7, 1951)

Date: October 2, 2010

"[Thoughts] just come and go and change shape like the clouds."

— Levy, Andrea (b. 1956)

Date: March 24, 2011

"It is like finding that cheese depends on chalk--that soul depends on matter."

— McGinn, Colin (b. 1950)