Bregretfullness ?

Couple of Brexit pieces today. Haven't had any of those for a while, and not without good reason.

First, one of the Guardian's better, more critical pieces. It's quite a long one but worth reading in full.

Matters came to a head in November 2021 at a weekly prayer group that Baker, a Christian, attended in Westminster. “I suddenly just started crying,” he recalled. “I couldn’t control it. I couldn’t speak. I was just clutching myself, sobbing my heart out.” One of the reasons that he was opening up about that now, he said, was that “I’m very conscious there’s lots of people out there who blame me for their misery. But it’s an unfortunate thing on this question of leave and remain that leaving has caused a great deal of anxiety and anger and depression for a lot of people. But being in the EU has caused a lot of anxiety and anger and depression for people…”

I really have very little sympathy for Baker, who is a colossally stupid individual; I care not much for his pointless misery. Exactly how “being in the EU” has ever caused anyone any anxiety or anger is never, never, not fucking once clearly explained with any form of any rationality whatsoever. All the same, credit where credit is due : we should welcome people who realise their mistakes. You don’t go on kicking someone after they’ve surrendered. That’s just malicious, and there’s no point in it.

(I would make exceptions for certain extreme outliers, however.)

If there is one certainty about the coming political conference season it is that considered arguments for and against Brexit will not be aired. The Tories will crow about Brexit being done. The Labour frontbench will solemnly observe that past tense, and avoid the B-word, as if it is a triggering trauma for the party and the country, best left undisturbed… “It’s become so divisive, that even raising the issue seems almost a provocative act. There’s a sense that we just can’t talk about this at all any more.”

Guilty as charged; I’ve barely mentioned it since it happened. Partly that’s because of The Event(s), but partly because I don’t feel it would do any good. There was a period in which it looked like a second referendum was a very real possibility - how close we really came I don’t know - but politics went for a general election instead. Since then there has been very little in the way of opportunity for a reverse. But no mistake, I still think it’s as stupid a decision as I ever did. It’s dumb. It’s idiotic. It’s cutting one’s throat to spite one’s arse, or something. I hate it. But for the sake of sanity, I also can’t dwell on it.

“A man with a conviction is a hard man to change,” Festinger wrote. “Tell him you disagree and he turns away. Show him facts or figures and he questions your sources. Appeal to logic and he fails to see your point. But suppose he is presented with evidence, unequivocal and undeniable evidence, that his belief is wrong: what will happen? The individual will frequently emerge, not only unshaken, but even more convinced of the truth of his beliefs than ever before. Indeed, he may even show a new fervour about convincing and converting other people to his view.” Welcome to Brexit.

Mmm. I saw somewhere something earlier about how in politics, one’s friends can sometimes be more dangerous than enemies… enemies expect to disagree with you, but friends expect you to be perfect or else.

About evidence. The data seldom if ever speaks for itself, but is rather subject to interpretation - we "read in" meaning, as with this very silly woman who thought that Netflix was calling her gay. But, as I've mentioned before, even so the data does speak for itself within one's own framework. If you voted Brexit because you wanted fewer trade restrictions, and actually now you find it's causes the opposite, then a rational person would begin to shift their stance. Not everyone is a true believer, but I'll get back to that at the end.

“Though we all have these underlying predispositions at the genetic level, to be a little bit more conservative or a little bit more liberal, these can be altered by environmental circumstances. And by far the most important environmental circumstances, if you’re a human, is your social milieu. If you’re an ant you can tell who is ‘us’ and who is ‘them’ with a very quick sniff. If you are a human it is more complex, and we put lot of work into that.”

To anyone interested in persuasion I can’t recommend Damon Centola’s Change highly enough. He perhaps overstates the case, but nevertheless shows that a lot of changing our minds is more about what everyone around us thinks than how we ourselves asses data directly. We operate more on metadata; if lots of trusted colleagues believe something, we probably will as well.

Beyond this it gets more complicated, but the basic method of changing beliefs boils down to something like this. First, you take a group of supporters of whatever position you believe in, and then you intersperse them with a (small) fraction of unbelievers. It’s vitally important that the believers get to talk to each other as well as the unconverted, this means they support and reinforce each other’s arguments as well as appearing more persuasive by number to the unconvinced. Then, you stick this group somewhere in the fringes. They must not be at the centre of a network but on the outskirts, because those at the centre - so-called “influencers” are actually only espousing the dominant view, they are not actually influencing but instead are the most subject to influence. So you keep your group away from this and let the idea spread around naturally, until those at the heart of it are more-or-less compelled to change. At least, that's what I remember off the top of my head.

It's time to bring in the second piece. Chris Grey notes that a consensus on Brexit does appear to be emerging : 

Thus, overall, there is a certain kind of consensus here, around three things: the vast majority of electors do not think that Brexit has been a success and the great majority of voters do not support greater divergence from the EU and the great majority of voters either support or at least do not object to the UK seeking a closer relationship with the EU....  a miserable 9% of the public think that Brexit has been a success. Far from solving any of Britain’s problems, Brexit is now itself a problem in need of a solution. So what might the solution be?

The short answer being, "there isn't a good one", except of course the very obvious one. Grey notes that of the solutions which have been proposed/tried :

For commentators and politicians who are not in power, it is easy to sustain that faith, but almost invariably, when in power, it becomes impossible to do so in the face of reality. That is why so many Brexiters, when given the power to implement it, went on to resign. Brexit Secretaries David Davis and Dominic Raab are both examples. They preferred to keep their faith intact rather than face reality, but others did the opposite and faced reality, for which the faithful inevitably despised them.

He goes on to discuss the polling in some detail, noting that, "re-joiners have more to do, but much to celebrate", and that however limited the polling change is, it's still something for us tofu-eating wokeratti liberals to take comfort in. 

According to some polls the preference margin to rejoin is considerably stronger than Grey reports : 63% to 37%, a 26 point lead ! Though, digging into the data, this is not a strictly accurate report. The raw numbers are actually 50% rejoin, 30% stay out - you have to take out all the rest (don't know, wouldn't vote, didn't answer) to get to the first numbers. Even so, that's still a 20 point lead for rejoin ! The 10 point lead in the same poll supporting actually having another referendum in the next decade is similarly encouraging.

For all that persuasion is difficult and that people assess claims in part by what everyone else thinks... they're hardly entirely data blind. If they can experience directly for themselves that things are not working as advertised, they do shift their stance. It's only the hardcore faithful who tie themselves in cognitive knots to reinterpret the evidence at least when it's literally right in front of their face; most ordinary people don't care about the Cause that much. Most such Causes are rather abstract to people, hence we get armchair villains and heroes alike - they might profess to believe something, vote for it, maybe even attend a protest... but they seldom directly experience its effects. When they do, I suggest, reality usually takes over.

The million-pound question is whether anyone should do anything about these results. "Never interrupt your enemy while he is making a mistake", Napoleon is supposed to have said, and indeed this swing has happened perhaps because of a lack of campaigning rather than in spite of it. If a major political figure were to jump on these figures and decide to run with it, it would certainly inspire True Rejoiners like me, but whether it would actually encourage or alienate the more casually interested in a very much harder to say.

What Rejoin needs, I think, is a pretext. We need some clear, simple event which would naturally prompt the question, "hey, wouldn't it be better to be back in the EU now ?". The cost of living crisis and the other Brexit-based failures are not quite enough by themselves for this. We need something more rapid and even more unambiguous, some major success of the EU that leaves us trailing, or conversely, yet another idiotic failure by the government where everyone can see the EU's approach is far superior. At that point, perhaps, a courageous (not in the Yes Minister sense) enough leader might have something to work with.

We'll see. Stranger things have happened. Then again, more likely things have failed to happen.

Calling Lizardshit

A short post to summarise two pieces I found, which I think quite nicely help explain why opinion polls sometimes come up with apparently large numbers of people believing batshit crazy ideas.

Incidentally... "bullshit" is well-recognised as meaning not caring about the truth, "batshit" seems already a standard way of emphasising the absurdly stupid, and "horseshit" appears to to generally used as a synonym of "outright lie". Do we need to add "lizardshit" as a term for "stupid poll making dumb statistical mistakes" ? Maybe.

But first, why lizards ? 

The lizardman constant, says the first piece, is the observation that a small fraction of survey responses are literally bullshit. That is, they are totally wrong for a wide variety of reasons : jokes, boredom, ignorance, insanity, mistakes, lazy, malice, innocent misunderstandings, idiocy. It gives numerous examples of which I will quote only a few here :

• 2% of Americans have “never heard of” institutions such as “the police” or the “U.S. Supreme Court”
• 7% say chocolate milk comes from brown cows and 19% that hamburgers come from pigs
• 6–8% of Americans think they could kill a grizzly bear, lion, elephant, or gorilla with their bare hands)
• 5% of atheists are “absolutely” or “fairly certain” that they believe in God
• 14% of undecided voters said Hillary Clinton might be a demon, but they might vote for her; 2% of Clinton supporters said she was and they would
• 1% of Brits who believe you should be imprisoned for 15 years (or more) if you ever fail to wear a seatbelt in your car

Needless to say, the actual fractions of the populace at large that believe in total hogwash like the above is likely orders of magnitude lower than the surveys suggest. That's the point, not that 5% - which appears to be a reasonable value for the Lizardman Constant - really do believe in lizard people.

Below a certain percentage of responses, for sufficiently rare responses, much or all of responding humans may be lying, lazy, crazy, or maliciously responding and the responses are false. This systematic error seriously undermines attempts to study rare beliefs such as conspiracy theories, and puts bounds on how accurate any single survey can hope to be... The reality is that humans don’t answer questions reliably, accurately, or honestly even close to 100% of the time, and shamelessly fail ‘common sense’ or ‘logic’ or ‘arithmetic’ questions all the time, requiring extensive precautions, careful survey design, and just throwing out a lot of data as garbage.

4-5% isn't so small. So when you get down to even, say, 20% or so, a significant fraction of those responses will be pure bullshit. This does not mean that surveys in general are full of crap, but more that any one survey might well be. If you want a more accurate result you need meta-surveys, asking different people in different places the same thing in different ways, etc.

Note also that "any one survey" is distinct from "every individual survey". They're not the same thing at all. Some individual surveys do get the right answers, and by way of example, I'll point back to that survey of Tory party members, a majority of whom would be willing to sacrifice their own party for the sake of Brexit. Lizardshit ? Methinks not, given that these were the same people who, subsequently, looked at the various leadership candidates squarely in the eye, and decided that the one with less staying power than a lettuce would be the one most suitable to lead the country.

On to the second piece*, which is a case study of a poll claiming that a quarter of Brits believe the coronavirus was a hoax. This is quite obviously nonsense, but the piece does a nice dissection of how to consider this finding critically. After mentioning Lizardman (only 9% said "definitely", which is not far off the constant), it takes a look at what "hoax" could mean to people :

* I already mentioned this before elsewhere, but felt I needed a more permanent record of it.

There’s a whole spectrum of heterodox views on Covid: those who question lockdowns, those who argue the virus was much less deadly than the medical establishment told us, those who believe governments used Covid as an excuse to enact authoritarian policies, all the way to the far more extreme groups of antivaxxers and those who believe the virus never existed in the first place... I bet a huge number of people answering the very vague question in the poll had other – perhaps still technically untrue, but far less outrageous – things in mind. 

And then it reports that a YouGov poll where the question was worded unambiguously gave numbers deep into Lizardman : 3%. But it goes further, asking to consider the implications of other numbers from the same poll :

7 per cent of people said they had already taken part in such a rally. If that were true and representative of the UK adult population (which is about 53 million: the 67 million total population less the 14 million under-18s), it would mean that something like 3.7 million people had already taken direct action and joined a protest against these supposed conspiracies.

What this is telling us is that this poll is seriously flawed in some way. It doesn't tell us exactly what the issue is, but clearly something is wrong.

The pollsters also asked the public whether they’d heard of the conspiracy newspaper the Light – the subject of a BBC article and podcast released this week. A surprising 14 per cent of respondents (7.4 million people, if that’s representative of the UK adult population) said they’d heard of the newspaper... of those who’d heard of it, 40 per cent said they were subscribers - if this was representative, it would mean that more than 2.9 million people in the UK subscribe to the Light – five times as many as subscribe to the Times. 

But of course, it’s not true. By the time you take 40 per cent of 14 per cent of the sample in the poll, you’re down to just 314 people, and all representativeness is out of the window.

Which is a simple, effective tip for considering if a poll is telling you something is meaningful or not. A poll of a thousand people might give you something truly representative on a clear-cut issue, but once it starts to get so some complex that it all fragments, numbers become unrepresentatively small very quickly. And that's without considering how the question was worded, how the sample was collected, etc.

I don't know if we really need "lizardshit" as a broader term for the problems specific to opinion polls, or if we can just get away with calling it a variety of bullshit. On the other hand, polls are so common, perhaps it would serve as a reminder not to take them on face value. Lots of people are undeniably very, very stupid... but generally nowhere near as much as most polls seem to suggest. And that's probably worth remembering.

Review : The Mind's Eye

Having been thoroughly impressed with both An Anthropologist On Mars and The Man Who Mistook His Wife For A Hat, I felt pretty confident that any other Oliver Sacks book would surely be well worth reading. So I picked up The Mind's Eye at my favourite local bookshop-bar some time ago, being determined to at last actually buy a book there and not just drunkenly peruse them as is my usual wont. And then it languished on my shelf for some time, I already being deep in my Tolkien binge at that point.

I'm afraid I have to say my ill-treatment of this (ultimately very satisfying) book continued. When I finally started it, I found it a slower burn than the others. The first few cases described are undeniably interesting but add nothing new to those covered previously. The way that we almost literally 'read' the world, assigning meaning to form and colour, is fascinating stuff, but simply repeating this without trying to understand it more deeply can quickly wear thin.

It didn't help that, now being on holiday, I naturally went on a book-buying spree. Prague has pretty good English bookshops but of course the selection back home is always better. So I did that rarest of things... I paused and... started another book. That's normally a death knell for anything I'm reading, the direct literary equivalent of eloping with a cheerleader.

(The analogy holds quite well, since my interest was diverted by a big, full colour, fully illustrated book on castles of the Welsh princes. Which is lovely, and you can read my review of that one here, but it certainly isn't worth blogging about.

I have no idea if this analogy makes sense to anyone else, but dammit it seems appropriate to me.)

After getting this shameful infidelity out of my system, I decided to resume TME. Fortunately from the point where I'd stopped it rapidly became more interesting. The theme is how mental imagery works, which for philosophy of mind is the equivalent of crack cocaine. And so once again, Oliver Sacks delivers. I'd give it a 7/10 overall; the early parts are not as interesting as some of his other stuff (at least if you've read his other works), but the later bits are if anything even more so. 

Face blindness

One of the first interesting cases is one of the simplest, prosopagnosia  : the poor ability to recognise faces. Of course everyone forgets faces from time to time, but this is well beyond the norm. In some extreme cases this can extend to one's nearest and dearest (or even one's own reflection !), but far more common is to simply have severe difficulties with more casual acquaintances. Sacks describes his own personal experience with this, and those of other academics. One went so far as to have a notice on his office door explaining that everyone should introduce themselves. 

Exactly how this happens is not well understood, perhaps because being bad at faces is so normal as to be barely recognisable as a disorder (Sacks compares it with dyslexia, which is about equally common but far more widely recognised), and can typically be circumvented. What I found interesting were cases where context helped a great deal, that if a "sufferer" saw person X at location Y, then they'd recognise them straight away, but have difficulties if they were in location Z. And that's very familiar; I've been caught out many times by seeing familiar faces in unfamiliar locations (who hasn't ?). Several times I've walked to or from work and the server at the local restaurant has waved at me, and only later have I realised who on Earth it was. Familiarity, Sacks notes, is not recognition.

It makes sense that the brain would have some dedicated functionality to recognising something as common and of such vital social importance as faces*. It also makes sense that something this specific could malfunction, or work sub-optimally. But the location-based aspect** reminded me of albatrosses, who completely fail to recognise their own chick if it falls even just outside the nest. This seems absurd, but clearly, prosopagnosia indicates that the human brain is not nearly so different from our feathered friends as we might presume. Our perception of reality is weird.

* And it partly explains my racist grandmother, because face recognition is learned early on. Reversing the typical western perspective : "One prosopagnosic colleague acquaintance, born and raised on China, went to Oxford as a student, and has lived for decades in the US. Nonetheless, he tells me, 'European faces are the most difficult - they all look the same to me.'"
**There seems to be also a correlation with having a bad memory for places.

Stereoscopy

The second interesting case is one of those exceedingly rare parts of Sacks which is wholly positive : the case of a woman regaining stereoscopic vision after losing it in infancy. In a previous book he describes how an operation ostensibly restored full sight to someone who had similarly lost vision completely at a very early age, but in that case, the results were almost tragic. The patient could only learn to see again with great difficulty, at first lost in a frustrating mass of meaningless colour and form. Just like learning to read, the information was there, but the meaning was not.

For the stereoscopic patient things were very different. Despite the prevailing medical belief that stereoscopic vision must be acquired before the age of two, the now middle-aged patient was essentially bestowed with fully normal depth perception. And this was nothing but beneficial, an endless delight to the patient to finally "see the space" between objects.

This particular patient was also a professor of neurobiology. In a direct analogy to Mary's Room, she'd told Sacks years before that she thought she had enough knowledge to imagine what stereoscopy must be like - but after the operation, she recanted, saying it was a wholly different experience. Stereoscopy turns out to be a qualia, something which cannot be adequately described but only experienced. Somehow this had never really occurred to me before.

The consequences of living without it also took me by surprise. True, this is just one aspect of depth perception, with a host of other factors also at work. But some, including Sacks himself, rely on this more than others (it seems stereo depth is experienced to different degrees, with some people reporting far more pronounced depth when viewing stereo images - pairs and stereograms and the like - than others). Without it the world feels like watching a movie or a painting, a continuous series of bizarre, Escher-like illusions with perspective being almost irrelevant.

I'm surprised that the differing focus of nearby and distant objects didn't destroy this effect, but it seems it didn't. Clearly this long-term effect is something qualitatively different from what one experiences if one merely closes an eye.

Hallucinations

Next, Sacks returns to his more usual bittersweet tone as he describes the early stages of his own eye cancer. I hesitated to read this. I deeply appreciate Sack's sympathy for and empathy with his patients, but my main interest is the philosophical implications, the distinctions and overlaps between mind and body. Reading for the sake purely of an emotional journey is really, for many reasons, just not my thing at all. To be blunt, I can't handle it and I don't want to.

But it's not like that. Somehow, Sacks maintains his usual style even here, and if it's necessarily more emotive than usual, the intellectual curiosity hardly plays second fiddle to this. Not for nothing is he called the poet laurate of neuroscience.

Sacks describes how his cancer caused a series of changes in his vision. With an operation to his retina, at first things seem to have been as one might naively expect : a central patch of darkness in his right eye. But as things progressed (sometimes improving, sometimes degenerating), the effects became much stranger. It began with simple hallucinations of abstract shapes, but rapidly turned to persistence of vision : "If I have been looking at something and then close my eyes, I continue to see it so clearly that I wonder whether I have actually closed my eyes."

This effect became astonishingly pronounced, but before that there were weird effects on colour. Colour vision was all but lost in the centre of his field of view in the damaged eye, with colours from the remaining peripheral vision suffusing into the centre - and of course varying hugely depending on whether he used his good left eye, right eye, or both. Having different colours available with each eye is strange enough, but it became weirder still. The blind spot would "fill in" based on the surrounding colours in "about a second or two" :

The next day I tested this with a blue sky and found the same result. The scotoma became as blue as the sky... when a flock of birds flew by, they suddenly disappeared into my scotoma, emerging on the other side a few seconds later - as if they had been cloaked in invisibility like a Klingon warship.

Colour was only the beginning. Like modern image-generative AI, the blind spot could fill in with patterns : brickwork, clouds, wallpaper... though not faces or other highly complex shapes. 

I started to think of my visual cortex not just as a rigid duplicating device, but as an averaging device, capable of sampling what was presented to it and making a statistically plausible (if not photographically accurate) representation of it.

After gazing at the bookshelves in my bedroom for a few minutes, I closed both eyes and saw, for ten or fifteen seconds, the hundreds of books arrayed in almost perceptual detail... I had the sense that my visual cortex was now in a heightened or sensitised state, released to some extent from purely perceptual constraints... These images or hallucinations have greater clarity, are more fine-grained, than perception itself, as if my inner eye had an acuity of 20/5 rather than 20/20.

I can at least dimly conceive of what this must be like. I too (Sacks was a big fan of stereoscopic imagery) appreciate stereoscopic vision experiences, mainly through VR these days, but I've got a couple of books of stereograms back home*. Viewing them, the sense of depth becomes somehow more pronounced, more "real" than in regular vision, in way that's not at all easy to articulate. Similarly, in very deep lucid dreaming, I get an experience of generating the imagery, a sense that things are somehow impossibly detailed.

* Though more recently I also have Brian May's Mission Moon 3D, which is not well written but does have wonderful stereo pairs.

Of course in Sacks case all this comes at an enormous costs. Besides the obvious, one of the stranger elements is that seeing can be quite literally believing. Eventually losing his peripheral vision in his right eye completely, Sacks describes how this is markedly different from having an eye patch : not only is the perception itself gone, but the whole concept of vision and the visual field is lost. He describes this also in patients who became fully blind and eventually lost mental imagery, or even the memory of visual experiences, absolutely. In his own case it was more limited but still severe : if something moved into missing field of view, for him it was almost as if it didn't exist. 

Then a voice to my right - her voice - said, "What are we waiting for ?". I was dumfounded - not just that I had failed to see her to my right, but that I had even failed to imagine her being there, because "there" did not exist for me. "Out of sight, out of mind" is literally true in such a situation... I am still in a world of suddenness and discontinuity, of sudden apparitions and disappearances.

Visual thinking

There is one interesting aspect to some of the earlier cases mentioned in the books. It's possible to forget how to read but not how to write. For some people this improves by doing the physical act of tracing the letters in the air. Another learned to trace the shapes of letters with his tongue, replacing reading with a sort of tongue-based writing.

The final section of the book returns to the more general case of this, considering how vision is integrated with thought. Sacks elaborates on the case of losing the whole concept of vision, describing how in one case this was seen as a "dark paradoxical gift", since the remaining senses were so much more heightened, in their own words to the extent of being, "a whole new order, a new mode of human being". But while it can and does happen - the idea of sensory compensation is practically a stereotype - it is not necessarily typical of actual experiences. It's also possible to go in exactly the opposite direction, not to lose mental imagery, but ironically to massively enhance it.

If Sacks hints at this with his own hallucinations, with the visual cortex having nothing else to do but make stuff up, in others this can be ruthlessly controlled. His own (sighted) mother could look at a lizard skeleton and mentally rotate it, accurately drawing it from different angles from her mind alone. But one blind psychologist used descriptions and his other senses to develop his inner eye to such a degree that it served as a full replacement for his eyes - accurately enough to replace the guttering on his roof !

"... to imagine, to visualise, for example, the inside of a differential gearbox in action as if from inside its casing. I was able to watch the cogs bite, lock and revolve, distributing the spin as required. I began to play around with this internal view in connection with mechanical and technical problems, visualising how subcomponents elate in the atom, or in the living cell."

Others experience imagery in more artistic ways, or as if shown on a screen, but all of the "visual blind" seem to have a far, far more intense and vivid experience of the inner eye than most of us do. There's also a connection to proprioception, with arms and legs being directly visualised as they move them. And this can apply to other senses as well, with a deaf lip-reader describing the experience as hearing, not seeing. Much like in this famous gif, I suppose.

Sacks also touches on aphantasia, the lack of mental imagery. Our visual imaginative capacity varies considerably between individuals, but I still find it extremely hard to grasp the concept of those who don't have it at all - especially for those with highly visual professions, like surgery and even artists (is a highly developed inner ear perhaps how Beethoven managed ?). Sacks, and some of the aphantasic themselves, suggest that they must be forming mental images somewhere, they're just not consciously accessible.

But are mental images really a sort of imagery ? It appears so. Studies suggest that summoning mental images takes effort and time and uses the same area of the brain as for visual perception. The final section of the book is very similar to Livewired, which to my shame I still haven't blogged yet*. Sacks notes that, as earlier, the brain is remarkably able to adapt, re-purposing the visual cortex in the blind to handle mental imagery more precisely, freed from the need to also process incoming signals from the eyes. This may be why it hallucinates when deprived of signals in the sighted as well as explaining how the blind can develop this to such a remarkable degree.

*Stuff keeps coming up. And unfortunately the book is so good it's hard to plan out a post that wouldn't just be reprinting the whole thing and get me sued for copyright.

In similar passages to parts of Sentient, Sacks describes sensory substitution, e.g. the blind using a cane to see the world around them, transforming touch and sound into a true mental picture (Sacks puts speech marks around some of these terms but I've decided it may be worth taking this literally). Again overlapping with Livewired, he describes tactile inputs sent to the tongue from otherwise ordinary cameras, allowing a crude but effective tongue-based vision. And it really does seem to manifest itself in the brain as vision, not just as a weird sort of touch.

Finally, at the very end he wonders if the congenitally blind could also be described to have true mental imagery. Here I think I have to disagree. He suggests that language is somehow able to overcome their sensory deficiencies and enable them to truly see with the inner eyes, albeit not understanding how this works. I think a simpler explanation would be that perhaps the brain isn't entirely live-wired; it doesn't figure everything out from pure experience, but comes with some initial draft of how to handle the basics of vision : shape, colour, distance, etc., leaving only the higher meaning as that which has to be learned. But who knows ?

I've long poo-poohed the idea that reality is "nothing like" our perception of it, all the while disparaging the foolish idea of materialism. Sacks' works make it abundantly clear that our perception is far stranger than we usually realise. 

The way I think I reconcile my opposing viewpoints - and I'm quite uncertain of my own opinion here - is as follows. Perception is that which our minds construct from our senses. Our sensory apparatus directly interacts with the world, but perception is a mental act. The brain is quite capable of making up stuff all by itself, but it's also capable of constructing it directly from sensory data, albeit into wholly arbitrary forms. Most of the time those worlds are separate, and usually the rendered internal worlds are self-consistent, but the brain is more than capable of making outright mistakes and constructing impossibilities. Hence the result is what it is : a glorious but mostly functional mess.