I Like Locke (II) : FREEDOM !

Welcome to part two in this mini-series examining John Locke's awesome Essay Concerning Human Understanding. In part one I attempted to summarise Locke's view on how we acquire near-as-damnit certain knowledge given our limited human frailties and imperfections. I found myself wishing I could invite Locke around for cake, because I found him to be commendably sensible. 

He says : we can know the world through perception, we differentiate reality from imagination because perception is involuntary, and some things cannot be known except through perception (e.g. you cannot imagine a colour you've never seen). Qualia exist in our minds but are induced by real properties of the objects. Some things we know through direct perception and intuition, while others we have to deduce, with reasoning allowing us to overcome our limited conditions. However, our true knowledge is still very limited indeed, with the vast bulk of our conclusions being only probable opinions, not certain facts. 

This all seems fine and dandy to me, so what, if anything, remains mysterious ? Time to look at that other great topic of armchair philosophers*, free will.

*As opposed to bathtime philosophers, obviously.

The matter of the mind

I'm going to put more of my own spin on this one than last time, so bear with me a little. Thanks to my efforts to wrestle with Locke, I realised I was finally able to articulate what I think free will means - and why I think this supposedly mystical concept is entirely compatible with the scientific world view. I'm mostly satisfied with my answer, so there.

I'm gonna approach this with the recurring topic of qualia. As I'm prone to banging on about, how can non-physical things affect reality ? Seriously weird. This is the "ghost in the machine" - a.k.a. mind-body problem of dualism. Concepts like yellowness, justice, number, and solidity exist only in our minds. They're induced by the outside world, but the concepts themselves, the descriptive labels, are purely mental. So do they really affect how we act, or are they purely passive, observable qualities ? If the latter, then free will would seem to be an illusion, with consciousness only being the act of experiencing the world and nothing much more than that.

Although sometimes mere observation does have consequences. Heisenberg would have approved of Ceiling Cat : he knows exactly what you're doing but has no idea why.

I have argued that such concepts are not purely experiential. When we see that something is yellow, we act differently than if it was red - even if our perception happens to be mistaken. Or if we see there are five cookies instead of the ten we were promised, we get upset and throw a hissy fit*. We act based on what we think we saw, not what we actually perceived. 

*Right ? 

Furthermore, there are clearly no "number" particles floating around in space any more than there are atoms of justice or molecules of mercy. Raw sensory stimulus is not enough - I need internal concepts on which to act. I need to know the exact number of those cookies, dammit. So although completely distinct from the physical world we see around us, these qualities are nonetheless "real" in some sense, and very much able to influence us at some level. Presumably they don't exist in some higher Platonic dimension (which would only shift the problem anyway), as they obviously have no direct impact except through our minds, but that impact is real enough all the same.

And besides : an illusory or purely observational consciousness wouldn't solve a bloody thing. That would mean that our minds can create a phenomenon radically different from anything else we've ever proposed. See, ordinary relational properties, like, say, relative velocity, though they do not exist as physical entities themselves, are at least labels of something physical. Their origin, what they represent, is clear. Even that most mysterious substance of dark matter is supposed to interact with ordinary baryonic matter through gravity. 

Mind you, in this documentary I saw about talking bears, it's apparently possible to talk to dark matter using a computer.

But the kind of "substance" proposed for consciousness in this strictly materialist scenario is radically different : absolute nothingness, something that can be generated, definitely exists, but has no power of affecting what generated it in the slightest. And even if consciousness itself were a purely relational property, a label for some specific interactions, that still wouldn't explain how we have awareness : why should some relational properties have an associated awareness and not others ?

Consciousness as an emergent, relational property sounds interesting at first, but in the end I think it's not that much better than illusionism. It doesn't explain at all how this process of experience, the distinct sensation of our inner mental lives, arises. It just says that it happens, somehow. All of our inner lives are apparently just pointless. Well, the hell with that ! My inner life is freakin' fantastic. What happens inside my head undoubtedly matters a great deal. To say that it doesn't is subjectively yet axiomatically wrong.

This is all getting a bit mystical and at any minute we might expect an armoured bear to appear, so it's high time to bring in Locke. He points out, rather nicely, that our understanding of matter is similarly flimsy :

When we talk or think of any particular sort of corporeal substances, as horse, stone, etc., though the idea we have of either of them be but the complication or collection of those several simple ideas [irreducible concepts we can only know through perception] of sensible [as in "senses"] qualities, which we used to find united in the thing called horse or stone; yet, because we cannot conceive how they should subsist alone, nor one in another, we suppose them existing in and supported by some common subject; which support we denote by the name substances, thought it be certain we have no clear or distinct idea of that we suppose a support.

I interpret this to mean that while we can know the properties of horses and stones in extreme detail, things come unstuck when we push this too far. Sure, we can bring in atomic theory and work out how molecules and suchlike can interact. But the very substance of matter itself... that's much harder. 

Example : what's a proton ? Some quarks. Alright, what's a quark then ? A character in Deep Space Nine... but you can see where I'm going this. We can have wonderfully thorough descriptions of matter, and on the large scale we can even have some pretty fantastic, genuinely meaningful explanations of how it behaves (sufficient for us to demolish cities, should we choose), but in some ways today's knowledge is no more sophisticated than that of Locke's era. The very essence of what matter is continues to elude us. And if matter is so challenging, little wonder that mind should be any different.

But we can put a far more optimistic spin on this. We know that something called matter exists. We also know, with even more certainty, that minds exist. Both are an intrinsic part of reality. Okay, we might never be able to describe their true nature with absolute certainty, but the examination of the possibilities is worthwhile all the same. Perhaps, if we're very lucky, we might achieve the same useful sort of theory of mind as we have for theory of matter - even if it is all, ultimately, built on the same shifting sands. Limited knowledge of atomic physics hasn't stopped us from building nuclear reactors, so why should limitations on our knowledge of our inner lives be any different ?

You know when you're bored and you start stacking random objects to make the tallest thing you can ? I call such towers "stuff detectors". They're extremely sensitive to the presence of stuff : vibrations, a light breeze, gravitational waves, boredom... but they're very impressive while they last.

So we should not shirk from seemingly "mystical woo-woo" ideas if that's where our inquiries take us; but neither should we rush to embrace Wicca or start sacrificing chickens to the Great God Gadzaookalgrump. Our aim is to consider, not conclude, no matter how outlandish. 

And especially to consider Locke's view, not the whole mighty philosophical edifice. Locke says, intriguingly, that whatever perceives must also think :

A man begins to have ideas when he first has sensation... To ask, at what time a man has first any ideas, and perception, being the same thing... it being impossible for anyone to perceive without perceiving that he does perceive.

We might wonder whether he really means that perception is directly equivalent to thought. Does a computer hooked up to a camera really "think" ? Does a calculator "think" ? What about a doorbell ? It "perceives" touch, after a fashion. But what he seems to be getting at is more tautologous : without inner awareness, you're not really thinking; true perception requires inner life. A lens doesn't "perceive" just because it affects light or projects it to a surface. I suspect Locke would say that of course an abacus or even a calculator doesn't "think", but he might come unstuck when dealing a computer. 

He might say, perhaps, that they have some form of thought but not the sort of conscious perception that we have. Locke believed that the soul (a.k.a. the mind) doesn't necessarily think any more than the body necessarily moves. So this at least opens the possibility of thought not being directly equivalent to perception; certainly our brain does unconscious information processing that we could happily label as "thought". While Locke says that "consciousness always accompanies thinking", I think he'd be open to revising this point and refining his definitions - especially given phenomena like blindsight. Merely processing data, or responding to external stimuli, isn't the same as thinking or having an inner awareness.

Being able to calculate the amount of force needed to bend a girder to 31 degrees is qualitatively different to being aware of the experience of applying that force.

Mind from matter, or matter from mind ?

Hang on, aren't we forgetting about free will ? Not really. As I see it, the essence of the problem* is whether we have, quite literally, mind over matter. And establishing that requires we fully understand what we mean by thought. If we don't understand the nature of thought, we can't possibly hope to say if it can or can't interact with matter.

* There are many caveats to what we mean by free will, of course. I'm only going to consider the strongest definition of the term, not some namby-pamby stuff like "unhindered" will, which is obviously for losers.

Locke, like Descartes, thought that mind was a kind of substance. He conceded that God could allow matter to think by itself, but his overwhelming preference was that mind was a kind of immaterial thinking substance. Here the jargon of the day is a bit obscure, but my impression is they took this rather literally. Not that mind was believed to be any kind of physical substance, which would be just plain silly, but nevertheless some immaterial, substance-like "stuff". When Locke says, however, that we have equally clear ideas of both mind and matter, we should remember his statements that we have no idea of what matter really is either (my emphasis) :

For putting together the ideas of thinking and willing, or the power of moving or quieting corporeal motion, joined to substance, of which we have no distinct idea, we have the idea of an immaterial spirit; and by putting together the ideas of coherent solid parts, and a power of being moved, joined with substance, of which likewise we have no positive idea, we have the idea of matter. The one is as clear and distinct and idea as the other : the idea of thinking, and moving a body, being as clear and distinct ideas as the ideas of extension, solidity, and being moved.

Locke never really gets any more convincing as to what a thought actually is. For my part, I don't think there are any fully satisfying descriptions, much less explanations. The idea of thought as utterly passive is as bizarre to me as the idea that I'm not really thinking what I think I'm thinking : this is to defy the very thing I'm most certain about of all. Yet if thought is not passive, it would appear to be virtually supernatural, with an inexplicable ability to effect, albeit in highly limited and specific ways, physical matter. Just how strange would this be ?

Not strange at all... as long as you're Keanu Reeves or Uri Gellar. And now I want a remake of the Matrix...

At this point it's probably worth a further digression from Locke to briefly review some of the major ideas about what consciousness actually is.

• Idealism. There is no "real" matter. Everything is consciousness; matter and the external world are all an "objective illusion".
• Dualism. Consciousness is distinct from matter. One variant of this is panpsychism, which says that consciousness is a fundamental property of all matter, so that everything has consciousness, at least to a small degree. Other variations are that consciousness is a field of some sort which can be received or generated by matter, but perhaps only by very specific configurations.
• Illusionism. Consciousness is some emergent property of matter but is at most entirely passive. It is pure observational experience. An extreme version seems to be that we're not even thinking at all.

I'm firmly a dualist, as was Locke. For my part I'm as certain that consciousness is not the same as physical matter as I can ever be certain about anything. But I'm much more reluctant to commit to anything beyond that.

Idealism, to be sure, is radical in the extreme. Frankly it feels like fixing a broken pipe by burning down the house, or in this case by spitting in the eye of God and running away shouting :

Locke would surely have welcomed a chain-smoking drunken robot into his philosophical mindset.

Even so, it's an elegant solution to the mind-body problem. We know with certainty that we can imagine matter : that is an incontrovertible fact. If anyone disagrees on this point, they are undeniably mad. But... we have no idea how matter can create mind. So, if it's all mind, there's no problem, whereas if it's all matter, things are horribly complicated.

 

This is all clever and interesting, but to me it's unhelpful. It's not obvious as to why our imaginary external world should be so damn consistent and testable. And who is the dreamer anyway ? I know it's not me, and it's probably not you : my sense of self is absolutely singular. This then requires consciousness within consciousness, which is getting weird and lacks any explanatory power - I cannot raise another consciousness within myself just by imagining it, that'd send me insane. Besides, I don't see how this solution is substantially different from saying, "a wizard did it". So while it's philosophically valid, certainly interesting, all the same it's just not for me, thanks.

Illusionism ? As already mentioned, to me this seems to be completely bonkers. Having seen back-and-forth arguments between the professionals, I'm very much of the opinion that is so monumentally self-inconsistent that it's one of the worst ideas anyone's ever had in any field whatsoever. It's not even wrong, so we shall say no more about this.

That leaves dualism. Panpsychism I don't think is terribly helpful as it says nothing much about consciousness comes to be, or how it interacts or combines when matter does the same. In this view consciousness is something that simply exists. There's nothing much that's obviously wrong with this idea, but what does it get us ? Very little, in my opinion. It in no way explains the dualistic nature of mind and matter. It's purely descriptive, not explanatory.

"Pan" is surely short for "pan-psychic". Didn't see that one coming, didya ?

So that leaves* the ideas that consciousness is something either generated or received by the brain. Furthermore, it's something that interacts with matter, but only via those very specific configurations of matter - possibly requiring a certain degree of complexity.

* Apart from the thousands of alternatives I'm no doubt unaware of.

My answer

In my view, the matter-generated version is the most scientific version of a theory of mind. We don't have to posit a pointless inner life of an electron, trapped forever in a subatomic coma. We don't have to pretend that our thoughts don't affect us despite the fact that they very clearly do. And we limit the interaction between mind and body strictly to the configurations of matter that generated it. Just as a lump of coal doesn't care a button about any magnetic fields that happen to be floating past, so most ordinary matter is totally impervious to whatever consciousness is. And just as a piece of iron does respond to magnetic fields - indeed cannot avoid it - so our brain must interact with our own mind. Rather satisfyingly, this view does not allow for telepathy or psychokinesis or ghosts or any other sort of woo-woo.

Surely, replacing the Ghostbusters with a bunch of philosophers is a golden opportunity for Existential Comics.

Of course, it leaves as a total mystery exactly how the mind is generated and how the interaction occurs, but this seems to me a very much better deal than saying reality isn't real or that electrons are all subatomic invalids. Common sense and science alike are saved. Hurrah ! 

And as a nice bonus, I think this view is entirely compatible with experiments where brainwaves are observed to change in response to external stimuli : sometimes our thoughts affect us, while sometimes physical affects our thoughts. Given that this scenario explicitly allows mind-matter interaction, we should fully expect this to work both ways. It also allows for consciousness to have different levels of complexity : the consciousness of a sleepy bear is not necessarily comparable with the consciousness of someone on LSD.

On the other hand, the other option is that matter receives consciousness as a kind external field (for want of a better word; consciousness might still be something radically different from any more familiar field). This definitely does allow for woo-woo, and makes it even less clear what consciousness is. Do each of our minds somehow exist separately in this literal field of dreams, or are they only disentangled by the brain ? What about memories ? We know, weirdly, that in some animals memories are not shared in different regions of the brain, but more on this later.

(In all this, however much hyperbole I might employ, however much I might dismiss ideas as madder than a bagful of mad clams that have just escaped from the Insane Asylum For Mad Clams, I can't be absolutely certain of anything. I'm just giving you my personal preferences, is all.)

That's my view then. Our brain (somehow) creates our mind (whatever that is) which interacts only with our own brain. That's what I mean when I talk abut free will : my thoughts control my actions but nothing else; they are not merely illusory products of electrochemical process in my nervous system. This is a full-throated view of free will without any magic at all. Oh, you can add in some magical sparkly stuff if you want - I won't stop you, you might even be right - it's just not necessary to do so. 

Locke's answer

But what about poor Locke ? Much like Mad Max in Fury Road, he's almost at risk of becoming a sidekick in his own post.

Since he was writing a magisterial treatise on knowledge and not a blog post, Locke carefully spelt out just what he meant by "free" and "will". The "will" aspect of the problem appears to be clear enough :

This power which the mind has thus to order the consideration of any idea, or the forbearing to consider it; or to prefer the motion of any part of the body to its rest, and vice-versa, in any particular instance, is that which call the Will. The actual exercise of that power, by directing any particular action, or its forbearance, is that which we call volition or willing.

So the will is just our capacity to try and make choices. Not the process of enacting the choice itself, because we could be in a straightjacket or paralysed or something. Which brings in the "free" part :

So far as a man has power to think or not to think, to move or not to move, according to the preference or direction of his own mind, so far is a man free.

Well, this is easy ! Free will is simply our capacity to make choices according to our own thoughts. Locke elaborates that not every action we take happens as a result of this. As a tennis ball, he says, has no preferences for choosing anything, so sometimes we might accidentally hit our friends without meaning to. Best to say away from Locke during tennis then, but the point is clear.

Locke elaborates that "free" is not quite the same as "voluntary", pointing out that you can volunteer to be imprisoned. Likewise "necessary" actions as those you cannot avoid. But while the case of physical action seems clear enough, I think it starts to unravel when it comes to thought :

A waking man, being under the necessity, of having some ideas constantly in his mind, is not at liberty to think or not to think; no more than he is at liberty whether his body shall touch any other or no : but whether he will remove his contemplation from one idea to another is many times in his choice, and then his is, in respect of his ideas, as much at liberty as he is in respect of bodies he rests on; he can at pleasure remove himself from one to another. But yet some ideas to the mind, like some motions to the body, are such as in certain circumstances it cannot avoid, nor obtain their absence by the utmost effort it can use. A man on the rack is not at liberty to lay by the idea of pain.

Which, contrary to Stoicism is not unreasonable. We cannot avoid having some thoughts and sensations, although thankfully being on the rack is no longer much of a concern*. This seems very much in agreement with the version I've outlined, but provokes an awkward question : what about those cases where we are, supposedly, at liberty to choose what to think ? What on earth does it mean to say we have control of our own thoughts ?

* I'm guessing Locke was a really, really vindictive tennis player.

The paradox of free will

Sadly Locke breaks off at this point into sophistry and semantics. He describes at some length how the will itself cannot have freedom - agents have freedom, not their properties. But he concludes, I think, very much in the affirmative that free will is a thing :

What is it determines the will ? The true and proper answer is : the mind. For that which determines the general power of directing, to this or that particular direction, is nothing but the agent itself exercising the power it has that particular way.

Okay, but... I've set out my case for why I think our thoughts do indeed control our actions. No problem there. But do we have control over our own thoughts ? Wouldn't that be a ghastly contradiction ? We'd have to think about what we wanted to think before we could think it, an infinite and tremendously confusing paradoxical chain. Locke at least asks the right question, but his answer is unsatisfying :

What moves the mind, in every particular instance, to determine its general power of directing, to this or that particular motion or rest ? And to this I answer — the motive for continuing in the same state or action is only the present satisfaction in it; the motive to change is always some uneasiness : nothing setting us upon the change of state, or upon any new action, but some uneasiness.

But what controls this uneasiness ? If our thoughts control our actions, but our thoughts are set by things over which we have no control, then free will would be rendered no more than a clever sham. Locke only partly comes to the rescue :

For all that we desire is only to be happy. Yet the satisfaction of any particular desire can be suspended from determining the will to any subservient action, till we have maturely examined whether the particular apparent good which we then desire makes a part of our real happiness, or be consistent or inconsistent with it. The result of our judgement upon that examination is what ultimately determines the main; who could not be free if his will were determined by anything but his own desire, guided by his own judgement.

So while things over which we have no control (in this case emotions) do influence us, they don't prevent us from making judgements. We can choose to put up with things we don't want in order to accomplish a goal, or to abandon that goal instead. We have a degree of control - limited but nonetheless important - over how we act and what will happen to us. We get to decide how to proceed with our goals. And even more fundamentally, it's we ourselves who get to "tell me what you want, what you really really want." We are not purely slaves to our desires.

Though teenage boys of the 1990s might happily disagree. Still, if we can't choose what our base desires actually are, we can at least judge for ourselves what they are - and how to respond to them.

In this sense free will is not unlike knowledge, as discussed last time. Truly certain knowledge is not possible - always there are assumptions about what we mean by certainty. But within those assumptions, we can recover certainty. For free will, we may not have total control of our desires - which would be a paradox - but we do have some. We get to choose roughly how to proceed, even if we can't choose exactly what it is we want in minute detail.

I think that some elaboration is useful here. In a previous post I've likened thinking to a process of beckoning. I do not choose exactly what I'm going to think, but I do choose what to think about : I beckon those thoughts toward me. Thoughts generally arrive in some complete, linguistically-structured form; I employ a process of active filtration on which to set down in text and which to discard. I choose. I do not choose the details of what my mind comes up with - I've no choice about that - but I do consciously choose which general areas to direct my attention towards. This is a bit like how I choose to wave my arm about. I choose where it goes, but I have no control of the fine details of the electrical signals sent through my nervous system. If I did, I imagine my hand would fly off, or something.

In some situations my conscious control is much more pronounced than in others. I don't have to think at all when walking around or shouting at pigeons. But if I solve a mathematical problem, or decide what to watch next on Netflix, or purchase something expensive, then my consciousness is fully in the driving seat. I can choose to override my base beliefs and intuition through objective analysis. And I can shape my desires through learning. I have a direct influence over my own future.

Consciousness is over-rated anyway.

Still, though, a difficult problem remains. In order for my thoughts to assemble themselves into neat, generally coherent sentences, a large amount of processing must be done unconsciously, i.e. at a level below my control. Occasionally, especially with complex issues, the general sentiment is raised to consciousness before crystallising into language. During this time I do have some control over exactly what I want to express. But even here, I have no control over that general sentiment, that vague, formless idea risen from the murky depths. There's a chicken-and-the-egg problem here - do I control what thoughts I have next, or do the thoughts I happen to have control what I do next ?

Maybe a simple thought experiment will help. Imagine a dot. Got it ? Good. Now move it around. What decided the direction of movement ? Well, you did, obviously, but how did you make that choice ? 

If someone else tells you, "move it to the left", then obviously you make a binary choice whether to obey them or not; you exercise your free will and control in making that choice (even if they say, "move it to the left or I'll jab you with this sharp pointy stick !"). But ultimately, with that dot being absolutely in your control, it isn't at all easy to say how you made a decision, any more than you can describe exactly how you wave your arm. Your options were essentially unconstrained. And by simplifying the question of free will down to this simplest of puzzles and finding it to be unanswerable, I think we can safely say that we're not going to fully solve this chronic mystery anytime soon.

So here's my view. Free will means our thoughts control our choices. We have limited influence over what our thoughts will actually be, but a degree of absolute control of our choices. Just as I don't pretend to have any clue as to how mind can operate over matter, so I leave as mystery how we can control our thoughts. I take this on a kind of faith, on which more next time.

All this has looked at what control actually is. Let's finish off with a look at who is in control. Just who or what is this "thinking substance" anyway ? And what about memory ?

If I'm in control, then who am I ?

The obvious retort is, "I think, therefore I am !" Yes, but who am I that's thinking ? Reading Descartes Meditations it's impossible not to follow along with Descartes walk-through guide to examining reality. I found that I became ever more certain of my belief that I am undeniably me. That is, in the thread of my life, the knot of awareness that is me was as much me 30 years ago as it is now, despite the myriad of different experiences between now and then. Memories are then just things which are added and subtracted from my identity, not my identity itself. There is something, however inscrutable, that is infinitely more fundamental to my identity than anything as petty as what I can recall. I may lose consciousness for a time, but when I regain it, there I am. The self is more than mere memory or even awareness. And it's this that solves the problem of split-brain animals having multiple identities.

Locke does not come up with a clear explanation as to what this mysterious "self" thingy is, but he has some interesting thoughts. He explicitly differentiates between the identity of living things and inanimate matter. Annoyingly, even defining identity for the latter is hardly straightforward :

If two or more atoms be joined together in the same mass, every one of those atoms will be the same : and whilst they exist united together, the mass, consisting of the same atoms, must be the same mass, let the parts be ever so differently jumbled. But if one of those atoms be taken away, or one new one added, it is no longer the same mass of the same body.

This is either obviously true or just confusing. If I take out one atom from a teapot, is it no longer the same teapot ? It has undeniably changed, even though its differences are for all intents and purposes imperceptible. 

Or even if the differences are perceptible. A kitty pretending to be a lion isn't fundamentally different because it's wearing an adorable mane.

Yet this feels somehow unsatisfactory; the change of a thing does not automatically equate with the destruction of a thing. After all, if the teapot were initially at rest, then suddenly accelerated to one hundred miles per hour, or its handle was broken, we'd only say the teapot had changed. We'd say it was the same teapot, just travelling very fast or without a handle. We wouldn't say the old teapot we knew and loved had suddenly ceased to exist, and been instantly replaced with a new high-speed broken-handled variant. But then how else should we define identity ?

Locke's answer is purpose. He seems content that when dealing with inanimate matter, atomic configuration is enough. When we come to plants and trees, however, he says their identity is quite different : it's the life that matters, not the atoms :

Partaking of one common life, it continues to be the same plant as long as it partakes of the same life, though that life be communicated to new particles of matter vitally united to the living plant.

He says the situation is much the same for animals, and makes the analogy of a watch : a configuration of matter ordered to a particular purpose. The major difference being, in his view, that the animating force of a watch comes externally, whereas for living animals the source is internal. Of course, the problem is that he has no clear idea what this "life" is, treating it as another sort of ethereal substance.

What of people ? 

Locke distinguishes between the identity of a man and the identity of a person*. The "man" is identified by his life force, or soul : "by constantly fleeting particles of matter, in succession vitally united to the same organised body." What he doesn't explain very well is whether this life force can be transplanted into other bodies and imbue them with the original identity. Or rather, I couldn't wrap my head around the various double-negatives and arcane uses of the different terms, so I couldn't pin down what Lock was trying to say about this. He either means it definitely is possible or definitely isn't.

*Queue angry hate mail from the woke brigade.

However, on personal identity there's no ambiguity in Locke - it's consciousness all the way. The consciousness is the self. The mysterious substance of consciousness doesn't change when we lose a limb or two. And even, "the same consciousness being preserved, whether in the same or different substances, the personal identity is preserved". Sounds like Locke would have approved of transhumanism.

Although possibly not.

Of course the tricky issue is memory. We can not only forget things, but also remember events incorrectly, and even "remember" things which never happened at all. One of the creepiest implications of this is, some argue, that we're constantly different people. Our continuous change, our nightly loss of consciousness, makes us a brand new person from day to day, minute to minute. 

Locke doesn't go to this extreme. Rather, he says that we're the same person as whatever we remember; that we forget things (or don't experience anything at all sometimes) doesn't change our identity, it just places gaps in it. So when Doctor Who regenerates, he or she is the same person even thousands of years after the initial. That there are gaps in the memory timeline doesn't mean we die each night and are reborn each morning.

But what if our memory was completely erased prior to some moment ? Here Locke does say we become a new person. If, he says, someone claims to be reincarnated with the soul of Socrates, but claims no memories of their previous life, then they are far all intents and purposes just being silly. If you can't remember your previous life, it obviously wasn't you who experienced it.

Here I have to disagree. This interpretation would shatter my singular self into thousands of pieces, or rather, turn my linear though gap-ridden timeline into a vast branching network. Working memory lasts at most a few minutes. So as I type this paragraph, my consciousness extends back for thirty-something years from long-term memory, but only about as far as the start of this paragraph in short-term memory. By the time I start the next paragraph, I'll have forgotten details of what I wrote here. So the "me" who wrote this will cease to be, but a new version of me will arise from the ashes of the old - even as the "me" derived from long-term memory persists and changes. There's a me that exists in the now, but the now is ever-changing, so the me in five minutes time won't remember everything that I do right at this moment. 

I just think this interpretation is a bit daft : the constant loss of petty details in memory doesn't seem grounds to say I have a new identity. And what about when I remember something I've forgotten ? If I can't happen to remember the name of the street of my favourite restaurant right now, but a minute later it pops into my head, I don't think anything has happened to my identity. I'm not about to turn every café owner out there into a potential identity thief.

A much, much better interpretation, in my view, comes from this article* :

There are many overlapping strands of psychological connection: personality, tastes, beliefs, memories, interests, preferences, desires and ambitions, to name a few. These are woven together like the strands in a rope. No one thread continues from one end of the rope to the other, and that’s to be expected. While the fibres that compose a rope are relatively short, they overlap, interlock and twist together so that the rope itself is strong and whole. The same is true of one’s psychological history: it is the time-spanning rope that ties together the different temporal parts and makes us complete.

* Which is ironic. For some reason the author wants to show that amnesia means the self is an illusion, but I think he presents a persuasive argument for the exact opposite conclusion.

I find this rope analogy compelling. It avoids the awkward old question of what becomes of a broom after both the handle and brush are changed, or a rock band after changing all the members. You can have a rope consisting of many interwoven threads, none of which extend through the whole length of the rope but it's unarguably one damn rope from end to end. There doesn't even have to be some mysterious inner core to wrap the threads around. It's enough that the rope is continuous, not that's made of the same materials throughout.

Interestingly, rope was used as computer memory for the Apollo guidance computer.

Locke allows this only insofar as the identity of the man, not the person. He says that this is even legally accepted, with someone suffering from temporary madness not being held accountable for their actions when restored to sanity. In his view, a man can be many persons. 

It seems simpler to me to say that a person can have many attributes, of which memory is just one. We don't need to say that someone who fornicated with a sheep because they were really drunk actually became a different person; rather, we can still say their responsibility was diminished but because their attributes were changed, not their identity. We don't say a person wearing stilts or clogs has a new identity, nor should we if they forget something. Just as a person wearing clogs can't be expected to be very good at ice-skating, so someone who's totally wasted can't be expected to be good at mathematics. Neither involves a change in identity, just attributes.

Perhaps an even better analogy would be a VHS tape. The tape can store many different things, and they don't need to be continuous. The tape might record a five minute weather forecast, a gap of an hour, and then twenty minutes of The Great British Bake-Off. What's on the tape is important. If we wipe it all and replace it with episodes of Rick And Morty, we've undeniably got something very different from when we started. But the tape itself remains the same.

How far could we push this ? Presumably at some point we do have to declare the tape broken or fundamentally changed. If we not only forget absolutely everything, but also change our whole personality, our intellect and morality, then at that point we might justifiably call ourselves a New Man. But the exact point at which this happens - if there even is one - is hard to define, and probably not all that interesting anyway.

......

So there we have it. I define myself roughly as the collection of my thoughts, memories, personality, morality, intelligence all other mental faculties I may or may not have. My thoughts give me a highly specific and limited kind of mind over matter, literal but utterly lacking any sort of mystical woo-woo whilst still being mysterious. We don't even need to mention the word "quantum" at all, nor ESP, nor illusionism. More interesting is the problem of how my thoughts interact, and in what sense I can be said to be in control of my own reasoning : how can I think what I need to think without first thinking it ? But this I am content to leave for another occasion. For now, I'm content in having set out my case for why free will is (a) real and (b) not in the least bit unscientific despite not being fully understood. 

Which all leads, of course, to the inevitably to the conclusion :

The version of consciousness I've presented has some definite consequences. We would never be able to program an artificial intelligence, for instance. We could get more and more elaborate forms of intelligence by this method only in the crude sense of data processing - but consciousness could never arise through pure number-crunching simulation. Genuine free will, consciousness, and emotion amounts to much more than randomness and unpredictable decisions under constrained options : it requires intention. And that, I submit, cannot occur through software but only specific, physical hardware. 

Not to say that there's nothing stopping us from building a true A.I., of course, just that we could never get one through code alone. In principle we could even test this : if we do ever manage to build a seemingly-conscious machine, we could recreate it in a simulation and it should, according to this idea, find that it would behave completely differently to its physical counterpart.

Next time I'll conclude this mini-series with a look at something a bit different : Locke's views on faith and revelation. If nothing else, Locke's insistence that faith must be rational ought to provide good fodder for provoking the antitheist brigade, which is always good for a laugh.