Sir Roger Penrose (born 8 August 1931) is an English mathematical physicist and Professor of Mathematics at the Mathematical Institute, University of Oxford, famous for his work in mathematical physics, cosmology, general relativity, and his musings on the nature of consciousness.
- There are two other words I do not understand — awareness and intelligence. Well, why am I talking about things when I do not know what they really mean? It is probably because I am a mathematician and mathematicians do not mind so much about that sort of thing. They do not need precise definitions of the things they are talking about, provided they can say something about the connections between them.
- The Large, the Small and the Human Mind (1997)
- Some years ago, I wrote a book called The Emperor's New Mind and that book was describing a point of view I had about consciousness and why it was not something that comes about from complicated calculations. So we are not exactly computers. There's something else going on and the question of what this something else was would depend on some detailed physics and so I needed chapters in that book, which describes the physics as it is understood today. Well anyway, this book was written and various people commented to me and they said perhaps I could use this book for a course Physics for Poets or whatever it is if it didn't have all that contentious stuff about the mind in that. So I thought, well, that doesn't sound too hard, all I'll do is get out the scissor out and snip out all the bits, which have something to do with the mind. The trouble is that if I did that — and I actually didn't do it — the whole book fell to pieces really because the whole driving force behind the book was this quest to find out what could it be that constitutes consciousness in the physical world as we know it or as we hope to know it in future
- Understanding is, after all, what science is all about — and science is a great deal more than mindless computation.
- As quoted in The Golden Ratio : The Story of Phi, the World's Most Astonishing Number (2002) by Mario Livio, p. 201
- Does life in some way make use of the potentiality for vast quantum superpositions, as would be required for serious quantum computation? How important are the quantum aspects of DNA molecules? Are cellular microtubules performing some essential quantum roles? Are the subtleties of quantum field theory important to biology? Shall we gain needed insights from the study of quantum toy models? Do we really need to move forward to radical new theories of physical reality, as I myself believe, before the more subtle issues of biology — most importantly conscious mentality — can be understood in physical terms? How relevant, indeed, is our present lack of understanding of physics at the quantum/classical boundary? Or is consciousness really “no big deal,” as has sometimes been expressed?
It would be too optimistic to expect to find definitive answers to all these questions, at our present state of knowledge, but there is much scope for healthy debate...
- Foreword (March 2007) to Quantum Aspects of Life (2008), by Derek Abbott.
The Emperor's New Mind (1989) 
- It seems to me that we must make a distinction between what is "objective" and what is "measurable" in discussing the question of physical reality, according to quantum mechanics. The state-vector of a system is, indeed, not measurable, in the sense that one cannot ascertain, by experiments performed on the system, precisely (up to proportionality) what the state is; but the state-vector does seem to be (again up to proportionality) a completely objective property of the system, being completely characterized by the results it must give to experiments that one might perform.
- Ch. 6, Quantum Magic and Quantum Mastery, p. 269
- What right do we have to claim, as some might, that human beings are the only inhabitants of our planet blessed with an actual ability to be "aware"? … The impression of a "conscious presence" is indeed very strong with me when I look at a dog or a cat or, especially, when an ape or monkey at the zoo looks at me. I do not ask that they are "self-aware" in any strong sense (though I would guess that an element of self-awareness can be present). All I ask is that they sometimes simply feel!
- Ch. 9, Real Brains and Model Brains, p. 383
- It is hard to see how one could begin to develop a quantum-theoretical description of brain action when one might well have to regard the brain as "observing itself" all the time!
- Ch. 10, Where Lies the Physics of the Mind?, p. 447
- Beneath all this technicality is the feeling that it is indeed "obvious" that the conscious mind cannot work like a computer, even though much of what is involved in mental activity might do so.
This is the kind of obviousness that a child can see—though the child may, later in life, become browbeaten into believing that the obvious problems are "non-problems", to be argued into nonexistence by careful reasoning and clever choices of definition. Children sometimes see things clearly that are obscured in later life. We often forget the wonder that we felt as children when the cares of the "real world" have begun to settle on our shoulders. Children are not afraid to pose basic questions that may embarrass us, as adults, to ask. What happens to each of our streams of consciousness after we die; where was it before we were born; might we become, or have been, someone else; why do we perceive at all; why are we here; why is there a universe here at all in which we can actually be? These are puzzles that tend to come with the awakenings of awareness in any one of us — and, no doubt, with the awakening of self-awareness, within whichever creature or other entity it first came.
- Ch. 10, Where Lies the Physics of the Mind?, p. 448–9 (p. 580 in 1999 edition)
Quotes about Penrose 
- Although I'm regarded as a dangerous radical by particle physicists for proposing that there may be loss of quantum coherence, I'm definitely a conservative compared to Roger. I take the positivist viewpoint that a physical theory is just a mathematical model and that it is meaningless to ask whether it corresponds to reality. All that one can ask is that its predictions should be in agreement with observation. I think Roger is a Platonist at heart but he must answer for himself.
- Stephen Hawking, in The Nature of Space and Time (2000) by Stephen W. Hawking and Roger Penrose, Ch. 1 : Classical Theory, p. 3