John Horton Conway

"When I was on the train from Liverpool to Cambridge to become a student, it occurred to me that no one at Cambridge knew I was painfully shy, so I could become an extrovert instead of an introvert."

"... I have said for twenty-five or thirty years that the one thing I would really like to know before I die is why the monster group exists.""

"[I]n two dimensions the... [19 point] hexagonal lattice solves the packing, kissing, covering and quantizing problems. ...[T]his ...book is ...a search for similar nice patterns in higher dimensions."

"We are planning a sequel... The Geometry of Low-Dimensional Groups and Lattices which will contain two earlier papers..."

"In this chapter we discuss the problem of packing spheres in and of packing points on the surface of a sphere. The problem is an important special case of the latter, and asks how many spheres can just touch another sphere of the same size."

"The classical... problem is... how densely a large number of identical spheres ([e.g.,] ball bearings...) can be packed together. ...[C]onsider an aircraft hangar... [A]bout one quarter of the space will not be used... One... arrangement... the face-centered cubic (or fcc) lattice... spheres occupy \pi / \sqrt{18} = .7405... of the total space.... the lattice packing has density .7405... . [H]pwever, there are partial packings that are denser than the face-centered cubic... over larger regions..."

"The classical... problem... asks: is this the greatest density..? an unsolved problem, one of the most famous..."

"The general... problem... packing... in n-dimensional space. ...[T]here is nothing mysterious about n-dimensional space. A point in real n-dimensional space \R^n is... a string of real numbersx = (x_1,x_2,x_3, ...,x_n).A sphere in \R^n with center u = (u_1,u_2,u_3, ...,u_n) and radius \rho consists of all points x... satisfying (x_1-u_1)^2 + (x_2-u_2)^2+ ... +(x_n-u_n)^2 = \rho^2. We can describe a sphere packing in \R^n... by specifying the centers u and the radius."

"There has been a great deal of nonsense written... about the mysterious fourth dimension. ...4-dimensional space just consists of points with four coordinates instead of three (...similarly for any number of dimensions). ...[I]magine a telegraph ...over which numbers are ...sent in sets of four. Each set... is a point in 4-d... space."

"[[w:Sphere packing|[L]attice packing]]... has the properties that 0 is a center and... if there are spheres with centers u and v then there are spheres with centers u + v and u - v... [i.e.,] the sets of centers forms an . In crystallography these... are... called s... We can find... in general n centers v_1,v_2, ...,v_n for an n-dimensional lattice... such that the set of all centers consists of the sums \sum k_i v_i where k_i are s."

"Why do we care about finding dense packing in n-dimensional space? ...This is an interesting problem in pure geometry. Hilbert mentioned it in 1900 in his list open problems... [T[he best packings... have connections... with other branches of mathematics. ..."

"[T]he best packings in up to eight dimensions belong to families A_n, D_n and E_n, and the corresponding s turn up in apparently unrelated areas... [I]n 24 dimensions the \Lambda_{24} has... connections with , s, and the Monster simple group... [O]ne day someone will write an article on "The Ubiquity of the Leech lattice." ...There are applications of... packings to number theory... [e.g.,] solving s, and to "the "... There are... applications of sphere packings... in digital communications... a typical question from... spread-spectrum communications for mobile radio... how many spheres of radius 0.25 can be packed in a sphere of radius 1 in 100-dimensional space? ...Two and three-d... packings... circles in a two-d... packing may represent s... in... a cable. Three-d... packings have applications in chemistry and physics... biology... antenna design... choosing directions for X-ray tomography... and... statistical analysis on spheres... n-dimensional packings may be used in... numerical evaluation of integrals... on the surface of a sphere in \R^n or in its interior. ...A related application ...n-dimensional search or approximation problems ...[I]n physics... dual theory and superstring theory... have involved the E_8 and \Lambda_{24} lattices and the related Lorentzian lattices in dimensions 10 and 26..."

"The densest possible packings are known for n \leqslant 8. ...\Lambda_n... represents a laminated lattice... the densest lattices in up to 8 dimensions..."

"Let me phrase the free will theorem that Simon and I proved. ...[I]f we... have free will... then so do elementary particles have their... very small quantity of free will... to mean, our behavior is not a function of the past. ...[I]f some experimenters have free will ...then so do elementary particles... even the ones outside us..."

"It's one of the things I most admire about Simon Kochen, my co-author, that... in August 2006, we'd been talking about this... for years... Suddenly the scales fell away, that had been obscuring the thing, and I said... "We've proved if we have free will, so do the particles" and he... said "Yes... this means that my stuff with Ax is all nonsense, doesn't it?""

"He'd been working with... Jim Ax for two decades on a theory that is now contradicted by... [our] . ...I admire Simon tremendously."

"Neither of us could have done it without the other."

"Lucretius... was an atomist, a follower of Epicurus. The original people who invented the atomic theory were and Democritus. ...Lucretius is discussing ...atoms ...he says, "at quite indeterminate times and places they swerve" ...because it allows for human free will... and "if the atoms never swerve... what is the source of the free will possessed by living things throughout the earth?" He says, "Although many men are driven by an external source, and often constrained involuntarily to advance or rush headlong, yet there is in the human breast something that can fight against it and resist it... So also in the atoms you must recognize the same possibility. Besides weight and impact, there must be a third cause of movement, the source of this inborn power... due to the slight swerve of the atoms... since nothing can come out of nothing." And then he goes on to say, "the fact that the mind itself has no internal necessity to determine its every act, this is due to the slight swerve of the atoms at no determinate time and place.""

"I find it... fantastic that somebody 2,000 years ago could have suggested that atoms... have free will."

"Most scientists until fairly recently are determinists."

"Descartes... his type of determinism is only partial. I call it disconnected... that the physical world and... our bodies, but not our minds operate mechanically... We're robots, but the mind is different... that "The will is by its nature so free that it can never be constrained." This is normally called Descartes' dualism... mind, soul or spirit, and matter... [M]atter operates according to one set of laws, and mind or spirit... to another."

"There are many varieties of . ...It says that there's nothing incompatible about determinism... and free will. ...This is from a dispute between Hobbes and.... Archbishop Bramhall... "A man was free, in those things... were in his power, to follow his will, but... he was not free to will..." The will was determinate, but that he was free. ...It's not contradictory, although it looks it at first sight..."

"Descartes' dualism... is explicitly contradicted by our theorem."

"[P]articles making choices... seems to involve deliberation. ...We are not pretending particles are conscious..."

"[L]ots of philosophical discussions about free will are concerned with the question of assigning moral responsibility. ...If the judge is a determinist, I might argue it was all determined. I just had to do it. I'm not responsible. ...We're not concerned with assigning moral responsibility... I want you to think of free whim..."

"I believe, and most people believe until they are educated out of this belief, that we are... free."

"I'm going to present arguments... to strongly support... that we do... have free will, but not... to prove it at the deductive level."

"[Leibniz] has this ... "that nothing happens without a reason why it should be so...""

"One consequence of the ... plus the assumption we actually have free will, is that even in the... inanimate world of particles, it's not true, this . A particle does one thing or another, and there's no reason... There's nothing in the previous history of the universe which tells it what to do."

"Laplace... wrote Mécanique céleste discussing the motion of the planets. ...[O]ne ...reason why ...determinacy got its ...impetus from the development of science, was that Newton's theory of gravitation ...was entirely deterministic. It left no room for freedom. ...Laplace, who did a lot of work on Newtonian ...theory says ...An intellect ...[or] intelligence, which knew ...where all the particles were at some moment and how fast they were moving, and so on, that every single thing could be known to that intelligence, provided a ...good calculator. ...It could reason out exactly what was going to happen in the future. ...It's the strongest ...assertion of determinism in the scientific literature. I don't believe it for one moment..!"

"The rise of determinism, it's just a consequence of the fact, science advanced tremendously, as a result mostly of... Newton and people like Laplace. They could determine things, but it's only the large scale science that ...seems ...deterministic. This century it's not been so."

"[S]omebody said, ..."We have to believe in free will. There's no choice." That's a nice ...sort of paradox ..."

"Dennis Overbye ...says ~everything we know of science convinces me ...that the world is deterministic, nevertheless I cling to the illusion of free will.~ (I'm not quoting his exact words.) ..~I can't run my life without this illusion.~ Some people have described it as a necessary illusion. We don't think it's an illusion ...It's not ...We think we have free will."

"[T]he arguments that suggest that we have free will can't be turned into logical deductive proofs. There's nothing wrong with that. If you argue in a court of law... we ...conclude, although we haven't got a proof, that probably the culprit was Mr. X."

"There isn't anything really, in the last resort that isn't inductive. Even the laws of deductive logic have been established only by induction. ...We can't use deductive logic ..."

"The consistency of determinism doesn't mean that it's true. Mathematicians are accustomed to have consistency proofs. They say nothing about truth. They just say something about what might be true."

"[Robert Nozick]: Philosophical Explanations "...it would be foolhardy ...to place ...significant weight upon the necessity or even truth of SR. ...Moreover theorems show that any theory that retains certain features of Quantum Mechanics also will not satisfye SR." SR is Leibniz's . ...[T]here's a reference to the Kochen-Specker paper ...in which Kochen, my co-author, and Specker ...both logicians, not physicists ...prove this ...From our point of view this is not enough. The is not as strong as the new theorem."

"The Free Will Theorem [s]ays roughly, that "if... humans have free will, then so do the elementary particles outside us. Uses three axioms SPIN, FIN, (or MIN) and TWIN." I only mean this in a very restrictive sense. I don't suppose much free will. The supposition is only that the human can choose which one of 33 buttons he want to press. ...[T]his choice affects the future history of the world in a minor way. ...We know that button was pressed ...before it was pressed we didn't know which one it was and ...a human experimenter has that much free will. That's the only amount of free will I suppose. We suppose nothing about these deep questions of moral responsibility and so on."

"[T]his Kochen-Specker paradox ...what it does ...[T]here's a problem in physics ...the measurement problem ...that's a wrong description. There's ...measuring the squared spin of a spin one particle. ...Let's say "measuring the spin" or measuring the [squared] component of spin ...of a spin one particle in a certain direction."

"Here's a particle, and I... direct my finger at it... and ask... What's it's spin in that direction? ...This particle is quantized. ...[I]t can only give two answers ...1 and 0. If I hadn't put that word squared in it could give three answers, 1, -1 and 0 ...Initially, it was... obvious... to believe that this concept existed before you measured it, but that was found not to be so. ...[W]hat the says is that it can't exist before you measure it... because there's no consistent set of answers to every question."

"When I was a little boy, I had two sisters... and we used to play ...and I had no moral sense ...when playing ...[I]f I thought that my sisters were getting near to my object, I changed ...the object ...[Y]ou have to select a new object which answers the ...questions ...already ...asked ...That's what the particles do. ...If you ask them this ...spin question, they don't have an object in mind. Think of a cleverer boy... who never bothers to select an object... just gives... answers at random, and then starts thinking what the object is. ...[T]hat's what the particles do. They don't have an answer in mind for each direction... [[w:Simon B. Kochen|[K]ochen]] and Specker proved that a long time ago... and the reason... is that there's a little puzzle... that puzzle has no solution. ...[T]hey use 117 directions, but ...Asher Peres ...reduced this set of directions to 33... [T]here's no conceivable set of answers... that's consistent with ...the spin law."

"[S]uppose I had a twin brother... [M]y sisters would have had a much better chance... [T]hey could... interrogate us separately... Then we can't change the object. ...Without transmitting information ...we couldn't win... [T]hat's what manages to happen in the particle case. ...[T]his ...Simon also thought of a long time ago.... but he didn't... deduce the ."

"[Y]ou've probably heard of the theory of relativity. ...Most of us have heard the assertion that you can't transmit information faster than the speed of light. Most of us... hear it on authority only. We don't really understand why not. ...The reason is ...there's no absolute notion of time. Time depends on which coordinate system you're using... on your frame of reference... As seen from one frame of reference, event A can be before event B and as seen from another frame of reference, event B came first. The world [universe] hasn't got a standard definition of time."

"I have a very simple way of explaining relativity theory... and if you follow that you'll understand how... it's impossible to... transmit information faster than the speed of light. The reason is, if you could, then seen from another person's point of view, you'd transmit information backward in time... [W]e would know the result of somebody's experiment before they performed it, and if they have free will... you'd know the result of their choice before they've made it, and they're free to make another one."

"[R]elativity is an important part of the game."

"[T]he strangest contribution of quantum mechanics to this discussion is the EPR paradox. ...That's an essential contribution to our theorem too. ...Despite the fact that information can't be transmitted faster than the speed of light, ...remotely separated events can be correlated ...and this is the content of our TWIN axiom, you can put two particles into a... singleton state... the angular momentum of the pair of particles is zero... [B]y the conservation of angular momentum... if you measure the angular momentum of this in any direction, then for the angular momentum of the other you get the negative answer, but... we're going to square it, that means... the squared component of spin is the same... [T]hese particles have been sort of hypnotized. If you ask... they will give the same answer... like I and my twin brother... [T]he funny thing is, even though the proves that the answers do not exist ahead of time, the equality of the answers can exist..."

"If I ask this question of this particle, and... my colleague on Mars asks the same question of the other particle, then even though those questions aren't determined, ...they don't exist ahead of time, ...they'll give the same answer. ...It's meaningless to compare the times at which we do it, because time is not an invariant concept. ...[I]f my colleague on Mars has asked the same question, or ...will ask the same question... or if he's now asking the same question... he'll get the same answer. That is the EPR paradox, the fantastic thing that Einstein thought would disprove quantum mechanics. It is... perfectly consistent, but ever since it was discovered people have been trying to explain it away... because it's hard to believe."

"[T]he proof of the Free will theorem... It's ...plausible ...from the start. ...Let's see ...the axioms SPIN, FIN and TWIN."

"TWIN... I just described... Even remotely separated particles... a condition in which, if asked the same questions, they will give the same answers. If they're not asked the same questions, all bets are off. ...We call that Twinning the particles ...an instance of ...entanglement."

"FIN [from finite speed] is the axiom... from relativity theory that information... can't travel faster than the speed of light."