The patterns of AI in the stuff of the future.

There’s a fascinating interview of Max Tegmark, a prominent physicist now focussing on artificial intelligence research, by Sam Harris (the well known atheist neuroscientist), broadly on the future of AI, in particular once it reaches the point of producing a generalised intelligence at least equal to that of humans.

There are too many points of interest for me to extract those and save you from the recommendation that you listen to the podcast, but a few points stood out to me.

Firstly, Max has apparently pretty much the same view as I have about ontology (i.e. the study of what is actually there at the most fundamental level); he even uses the same language as I’ve been doing. I suppose that as we are both physicists at root, this is not as surprising as it might seem (I’m pretty sure he hasn’t read what I write, and I’ve not read anything he’s written!) There is “stuff”, and there is pattern, and pattern is not heavily dependent on the stuff which bears the pattern – as he puts it, pattern is substrate-independent. He points out that wave equations later adapted to describe fundamental particles were originally developed in fluid mechanics; the mathematics describes this class of patterns (which happen to be dynamic patterns) irrespective of whether they are in water or in, say, the electromagnetic spectrum.

He moves rapidly from there to discussing how AIs of the future are likely not to be using electrons in solid state systems, they could be in something entirely different – but the patterns will be transferrable, and in the process mentions that in IT there is one basic element, the NAND gate, which he likens to synapses in the human brain. However, of course, you can construct a NAND gate out of all sorts of “stuff”…

The bulk of the interview is about how we might control intelligences we create which could be far greater than our own intelligence, but there are many directions in which they could have gone but didn’t. Can we hope, sometime, to upload the pattern which is “us” to a computer, and thereby defeat death, or at least the limited lifespan of our biological substrate? Mention was made of the fact that the best chess player is now not a computer, after the famous defeat of Gary Kasparov, but a human-computer team, which Max calls an “android” – probably correctly, as it is a human-machine combination. Might we augment ourselves and become amalgams of human and machine? (As I get older, I would very much appreciate some memory augmentation, perhaps a few terabytes…)

What, morally, is our position regarding a machine with a generalised intelligence greater than ours? Is it morally acceptable for it to be effectively a slave? (There is some discussion of this, but by no means exhaustively). If not, will we see a situation, as Sam and Max discuss, of the superhuman intelligence being, in effect, in the position of an adult surrounded by young children, unable to make decisions as good as the adult?

If I have one overwhelming worry about this prospect (and it is closer than we might think – the self-driving car is already with us, the military are playing with machines which may, Bond-like, have a “licence to kill”, and the cheapest calculators can perform calculations many times faster than even the fastest human, giving a glimpse of what the situation might be were their “intelligence” generalised rather than restricted to arithmetic), it is that we are biological systems, and as such have emotions – and emotions are what founds most of our moral behaviour (as well as some of our most immoral). Without emotion, can an artificial intelligence ever be trusted to make good moral decisions? I worry about that; my long period of depression, which ended in 2013 (deo gratias!) ended up in a state of anhedonia, in which, broadly, I did not feel emotions. I could assess what would happen if I did something fairly well – my computing power wasn’t seriously damaged – but I couldn’t make a decision as to whether actually to do it or not because there was no emotional charge giving me this instead of that course of action. Even the prospect that the action would damage me, perhaps kill me (or others), had no emotional charge – it was a matter of indifference whether I were injured, or in pain, or dead in the future.

I got through that period by following a set of rules, largely “act as if” rules. Others did not get damaged, other than perhaps emotionally, and I got damaged relatively little and am still here to write about it. But it could so easily have been different.

Would a super-AI have the same problem? If so, we would want there to be VERY strong “rules” imbedded at an early stage to avoid disaster.

But then, I took much the same view when raising children…

Imaginary friends…

There’s a new attempt to claim that the existence of God is rationally probable kicking around at the moment, divided into five “reasons”.

Therer’s a general problem about all of these, in that while they may point to there being something which we don’t yet fully understand underlying existence, the directions the author is going in would lead to a “God of the philosophers”, which (as I’ve complained regularly) looks nothing like the God of the Bible. In fact, it looks a lot more like Stephen Hawking’s “Theory of Everything”, and while I would be absolutely fascinated to see Hawking or some other brilliant mind come up with such a theory, and I would no doubt regard it as wonderful, awesome and similar words, I can’t see myself worshiping, loving or having allegiance to a theory.

I may come back to the other four reasons, but at this point I want to talk about the first, which has been called by others “the unreasonable effectiveness of mathematics”. The link I use there refers to a number of objections by Richard Hamming, but the list of names who have regarded this as a puzzle which requires answering includes some very great thinkers, and I don’t think it can be dismissed out of hand. As Max Tegmark suggests, perhaps at a fundamental level everything IS mathematical. It is definitely the case that mathematics comes up with concepts, and those concepts later find use when some theoretical scientist realises that that piece of maths describes (at least reasonably well) the mechanism which they are studying. The use of the Riemann mathematics in General Relativity, rather a lot of years later, is indeed a fine example.

I am not going to set out to dismiss the idea, but I do see a number of problems (apart from the fact that equating God with mathematics would negate virtually every religious or spiritual writing in history). Hamming mentions one, which I think has a lot of force – mathematics continues to produce a load of concepts, and not all of them by any manner of means manage to find a natural mechanism to describe. Some of them don’t describe the mechanism particularly well – I would argue, for instance, that string theory (which is an admirably complex piece of mathematical thinking) doesn’t actually describe the fundamental state of matter particularly well, given that to date it has failed to make any prediction which could be tested and that it keeps on being modified by legions of theoretical physicists in the hopes that one day it might.

He then develops that (it’s listed as a separate objection, but I think it flows from the above) to argue that we use the conceptual tools we have (which are, in science, largely provided by mathematics) to try to explain things. If we lack a mathematical concept for something, science doesn’t explain it, at least not yet.

What concerns me more, however, is the fact that mathematics throws up concepts which have no physical correspondent. Infinity is one such; we cannot observe an infinity; if we could, it would not be an infinity. It (together with a class of mathematical concepts which are quasi-infinities, called “transfinites”) is incapable of being experimentally verified; they just result from a contemplation of what would happen if an operation which you can perform a lot of times were continued indefinitely. I’ve written elsewhere of the problems faced by referring to attributes of God such as omnipotence and omniscience as infinite; I am deeply uncertain of the wisdom of this habit of saying “well, it looks as if it’s going there” without actually doing the experiment, as concepts have a habit of breaking down in limit conditions.

However, there’s another mathematical concept which cannot exist in the real world at all (it isn’t just not verifiable by experiment, it cannot exist) and that is the square root of -1, called “i”. The definition is i2 + 1 = 0. It is actually called an “imaginary number” for just that reason – it can have no real world equivalent. Mathematics therefore (arguably) axiomatically overspecifies what actually exists (axiomatically as opposed to the as-yet-unused mathematical concepts which may find an application some day).

I grant you, a very common use of imaginary numbers is in complex numbers of the form a + bi, where a is the “real” and bi the “imaginary” part; the imaginary part is then thought of as somewhere on an axis at right angles to the real axis. Any point on a two dimensional graph can therefore be represented as a single complex number.

The thing is, imaginary numbers are all over the place in some fields of mathematics, notably in areas like Rieman spaces (mentioned above) and anything to do with waves, including quantum physics. The mathematics for things which do exist therefore relies on concepts which don’t and can’t exist, despite the comments of the mathematicians talking with Melvyn Bragg in this BBC programme.

There are, I suppose, two ways of looking at this. The first is to say that mathematics clearly includes nonexistent things, and therefore cannot demonstrate the existence of God, because, well, God exists and they don’t.

The other is to say that if, just perhaps, there is something in the author’s argument that mathematics can tell us something about God, it is that “God exists” is at best a deceptive statement – because God includes some aspect which is, strictly speaking, imaginary…

So, my atheist friends, forgive me if I laugh at your comments about God as my “imaginary friend”. You’re reading this courtesy of techology which relies on imaginary numbers to exist.

Uncaused causes…

I found a piece on my FB feed today on the origin of the universe, written by a Physicist. “What was the cause of the Big Bang?” it asks.

I find it slightly surprising to find that from a Physicist, to be honest. The author will know well that if there was indeed a “Big Bang” (and it seems overwhelmingly likely that there was, despite the criticism that it has to have been a “one off” event which can’t be replicated so as to produce additional experimental data), the mathematics of the situation demand that there be a singularity at the origin, a point beyond which there is no space and no time.

I’ve become used to the question from laymen “So what caused the Big Bang?”. Everything we experience in normal existence, after all, seems to have a cause, and this is a cataclysmic event which we detect at the earliest point in time.

The thing is, the whole notion of cause demands that there be event a which causes event b, and event a has to be before event b, i.e. earlier in time. When it comes to the Big Bang, however, there is no “earlier” to look at. The idea of “earlier” is impossible, and so the idea of a cause for it is equally impossible.

That can require some getting the head around for most of us. However, in the case of a Physicist, ideas of the random (in which you cannot say something was “caused” because the same supposed cause could have produced a variety of results including the one observed) are prominent. So is the concept of the “Dirac soup”, an universe of elementary particles in which particles pop into existence and out of existence on a purely statistical, random basis; that too seems to be experimentally verifiable.

More even than that, however, is a set of observations in particle physics which seem to give the lie to the whole concept of causation; particles can influence each other at a distance simultaneously, being “quantum paired” and a change in circumstances can actually have an effect earlier than the cause (in the case of this experiment by altering the situation after a particle has passed a double slit).

In the circumstance, it surprised me a little to find a Physicist writing about the “cause of the Big Bang”. Clearly there was and could be no “cause”, because time as well as space just “happened”.

Theologians will probably want to say that as God is atemporal, a cause remains possible. The thing is, “cause” is still an incoherent idea unless one postulates another time-like dimension experienced only by God, and at that one to which God is subject, i.e. experiences as a constraining factor. I suspect most theologians who go down this route are not going to want to concede that God can be constrained by any dimension… If, with God, there is no “before” and no “after”, then with God there is also no “cause”.

And yes, I know this all throws a huge spanner in the concept of God as creator, at least if you interpret it as “creatio ex nihilo”, creation out of nothing. The concept of creation, too, is a time dependent one. I can see little option but to think in terms of creation as a process in which God may well be involved (and I am confident that whatever it is that is God is fundamental to that process), but which it is impossible to say that God originated.