Quality vs. Quantity

It’s an old saying, usually coming straight from the lips of the slightly insecure or self confident: ‘I do quality, not quantity!’. It’s a very appealing idea, the concept that skill and ability can mark one out from pure brawn and throwing vast amounts of resources at a problem. But sometimes quality is not the answer. Sometimes quantity is the way forward: and to illustrate this, I’m going to tell a story.

The Industrial Revolution was the biggest, most tumultuous and most difficult period of transition that the western world has ever been put through, and design was no exception. Objects once made individually and by hand, the work of skilled craftsmen, were now produced using vast steam-powered machinery owned and directed by rich businessmen. And being businessmen is the key here; they wanted their products to sell to the general public, and the only real way they knew how to do that back then was to make the things cheap. This generally manifested itself in making products as simple to produce as possible using the machinery of the day, and the idea of ingratiating design elements into these processes didn’t register on their conciousness; perhaps rightly, since the majority of the populace being sold to were rather poor and may not have been able to afford the prettier, more expensive item. What this did mean was that the products ordinary people filled their homes with were usually large, since Victorian machinery couldn’t handle high tolerances too well, decorated in a rather gaudy, ‘tacked on’ fashion rather than having beauty as part of the design, and were often of a very poor quality as manufacturers skimped on materials and good processing. We must remember that this was the golden age of deregulated industry, companies having no responsibility to either adhere to standards or treat their low-paid, overworked and awfully treated workers with any degree of respect.

This state of affairs was deplored by John Ruskin, an art critic and thinker of the time. He argued for a return to the old ways of doing things, with small-scale industry taking the place of big business and simple, good-quality, hand-crafted products replacing the mass-produced goods of the Victorian age. Since he actually had other things to do with his time, he didn’t expand on this plan to any great degree; but a man named William Morris did. Morris was a designer whose textiles designs would make him rich and whose poetry would make him famous, but he latched on to Ruskin’s ideas whilst at university, and they turned him into an early socialist. Indeed, he spent a decent chunk of time in later life standing on street corners distributing socialist pamphlets, but that’s another story. Morris took Ruskin’s ideas and, with a group of like-minded friends, founded a new design movement based on Ruskin’s philosophy. They wanted a return to craftsmanship, to put skill back into design and for workers to ’empower’ themselves through the making of good-quality, appropriately sized, simply designed products, putting them in charge of their own lives rather than acting as slaves to the corporation. More than that, they wanted to reinstate the role of design as a fine art, putting beauty into everyday products for everyday people, and to advance the art of design in general. This movement would later become known as the Arts and Crafts movement.

This movement was around between around 1860 and 1900, and enjoyed some success in revitalising design as an art form. Various universities and other intellectual establishments began founding schools of design, and as the Industrial Revolution wore on even the capitalists began to take notice of these new ideas, realising that the common people could be persuaded to buy their products because they were designed well rather than just because they were cheap. And what about the Arts & Crafts philosophy? Well, a few organisations were set up promoting just that idea, trying to bring together skilled craftspeople into a setup styled as a medieval guild. And they totally bombed; the production of individual, hand crafted items took so many more man-hours than the industrial mass-production process that simple economics (then a rather under-developed field) dictated its price was far beyond the price point of the ordinary people Morris’ philosophy aimed to serve. Whilst the products they produced were undoubtedly beautiful, and advanced the art of design considerably through their use of unusual materials and craft techniques, producing such quality products was simply not a viable solution to providing for the common man.

Indeed, it wasn’t until the 1920s that a design movement finally managed to make itself felt among the common people. In Germany, the Bauhaus school was set up in Weimar (home of the titular new republic that would be replaced by the Nazis in 1933) and began educating designers in all aspects of craftsmanship and fine arts, something that William Morris would doubtless have agreed with. However, the reason that the Bauhaus style proved so internationally successful, and continues to be relevant today, is for its acceptance of the machine age, and for experimenting with techniques from an industrial, rather than crafts, background. A good example is tubular steel; in the 1920s, extruded tubular steel (without joints in it) was a new innovation that was much stronger than previous efforts. Bauhaus designers immediately began experimenting with it, and when Marcel Breuer designed his Model B3 chair (later known as the Wassily chair) based around a tubular steel frame it put the material, and the chair, on the map. Here was a style whose products could be produced on a large scale, making them globally famous, and the style flourished because of it. Even today, products can be bought based on Bauhaus designs or in the Bauhaus style, and whilst many of William Morris’ wallpaper prints are still available, they are all now mass-printed in factories. He must be turning in his grave.

This is just an example, but it successfully illustrates a point; that, on a large scale, going too far into the quality side of things simply isn’t sustainable if it comes at the expense of quantity. It just comes down to the economics of the problem; the consumer culture gets blamed for a lot of things, but the extent to which mass-production has made ‘luxury’ goods affordable to the common people and made all our lives more comfortable is frequently neglected. Quality at the expense of quantity is rarely the answer; best, of course, is trying to find a way to do both.

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Plato’s Cave

Everyone’s heard of Plato, to some extent anyway; ‘Greek bloke, lived quite a while ago, had a beard’ is probably the limit of what could be considered universal knowledge. This he most certainly was, but what made him famous was his work, for Plato was taught by Socrates and was one of the finest philosophers and thinkers to grace human history. His greatest work was ‘The Republic’, a ten book piece exploring the nature of justice and government through a series of imagined conversations, hypothetical situations, metaphors and allegories. ¬†One of these allegories has become especially linked to Plato’s name, which is somewhat surprising given how little the actual allegory is known to the world in general, so I thought I might explore it today; the allegory of the cave.

Plato believed in a separate level of reality, more fundamental than the physical world we encounter and interact with using our body and senses, that he called The Forms. To summarise briefly, a Form is the philosophical essence of an object; in the real world, a shelf is three bits of wood and some nails all joined together, but the Form of this is the ability to store some books within easy reach, for example.  Without the essence of shelf-ness, the shelf literally is nothing more than some wood, and ceases to be a shelf on a fundamental level any more. Similarly, when we turn a piece of plastic into a toy, we have fundamentally changed the Form of that plastic, even though the material is exactly the same.

Plato based most of his philosophical work around his Theory of Forms, and took the concept to great extremes; to him, the sole objective scale against which to measure intelligence was one’s ability to grasp the concept of the Form of something, and he also held that understanding the Form of a situation was the key to its correct management. However, he found his opinions on Forms hard to communicate to many people (and it can’t have helped that he was born to a rich family, where he was given plenty of opportunity to be intelligent, whilst many of the poor were uneducated), and some considered him to be talking rubbish, and so he came up with the allegory of the cave to explain what he was on about.

Imagine a large group of prisoners, chained to the wall of a cave for some unspecified reason. They are fixed in position, unable to move at all, and their necks are also fixed in position so they cannot look around. Worst of all, however, they have absolutely no memory of the world or how anything in it works; in many ways, their minds are like that of a newborn toddler trying to grasp the concept of the world around him. Everything they are to know must be learnt from experience and experimentation. But in front of them, they can see nothing but bare rock.

However, there are a few features of this cave that make it interesting. It is very deep and comprises multiple levels, with the prisoners at the bottom. On the level above the prisoners, and directly behind them, is an enormous fire, stoked and fed day and night (although being at the bottom of a cave, the prisoners don’t have any concept of day and night), brightly illuminating the wall that the prisoner’s see. Also on the level above, but in front of the fire, is a walkway, across which people walk along with their children, animals and whatever items they happen to be carrying. As they cross in front of the fire, their shadows are cast onto the wall the prisoners can see, and the sounds they make echo down to the prisoners too. Over time (and we’re presuming years here) the prisoners get used to the shadows they see on the wall in front of them; they learn to recognise the minute details of the shadows, to differentiate and identify them. They learn to call one figure a man, another a woman, and call others cat, dog, box, pot or whatever. They learn that sometimes it gets cold, and then hot again some time later, before reverting back to cold (thanks to the seasons). And then, they begin to make connections between the echoes they hear and the shadows. They learn that man shadows and woman shadows talk differently from one another and from dog shadows, and that basket shadows make hardly any noise.

Now remember, we’re presuming here that the prisoners have no memory/knowledge of the ‘real world’, so the shadows become, to them, a reality. They think it is the shadows of a dog that make the barking sound, and that when the shadow of a clay pot is dropped and breaks, then it is the shadow that has broken. Winter and summer are not caused by anything, they merely happen. What is to us merely an image of reality becomes their reality.

Now, Plato has us imagine we take one of our prisoners away; free him, show him the real world. As he says, if we suppose “that the man was compelled to look at the fire: wouldn’t he be struck blind and try to turn his gaze back toward the shadows, as toward what he can see clearly and hold to be real?” Wouldn’t he be simultaneously amazed and terrified by the world he found around him, to see a fully-fledged person causing the shadow he had once thought of as a fundamental reality? Perhaps he would be totally unable to even see, much less comprehend, this strange, horrifying new world, unable to recognise it as real.

However, humans are nothing if not adaptable creatures, and after some time ‘up top’ our freed prisoner would surely grow accustomed to his surroundings. He would see a person, rather than their shadow, think of putting something in a box, rather than seeing a black square on a wall, and would eventually feel confident enough to venture out of the cave, look at and comprehend the sun, and eventually even recognise it as “source of the seasons and the years, and is the steward of all things in the visible place, and is in a certain way the cause of all those things he and his companions had been seeing”. (Plato often used the sun as a metaphor for enlightenment or illumination from knowledge, so here it represents the prisoner’s final understanding of the nature of reality).

Now, our prisoner could be said to be educated in the ways of the world, and after a time he would surely think back to those long days he spent chained to that wall. He would think of his fellow prisoners, how piteous their lives and their recognition of reality was when compared to him, and how much he could teach them to aid their understanding and make them happier. “And wouldn’t he disdain whatever honours, praises, and prizes were awarded there to the ones who guessed best which shadows followed which?”. So, Plato has our man return to his cave, to his old spot, and try to teach his fellow prisoners what reality really is.

And it is here where Plato’s analogy gets really interesting; for, rather than accepting this knowledge, the fellow prisoners would be far more likely to reject them. What are these colour things? What do you mean, stuff goes ‘inside’ other things- there are only two dimensions. What is this big fiery ball in this ‘sky’ thing? And, after all, why should they listen to him; after so long away, he’s going to be pretty bad at the whole ‘guessing what each shadow is’ business, so they would probably think him stupid; insane, even, going on about all these concepts that are, to the prisoners, quite obviously not real. He would be unable to educate them without showing them what he means, because he can’t express his thought in terms of the shadows they see in front of them. If anything, his presence would only scare them, convince them that this strange ‘other world’ he talks about is but a feat of madness causing one’s eyes to become corrupted, scaring them away from attempting to access anything beyond their limited view of ‘shadow-reality’. As Plato says, “if they were somehow able to get their hands on and kill the man who attempts to release and lead them up, wouldn’t they kill him?”

To Plato, the world of his Forms was akin to the real world; true, enlightened, the root cause of the physical reality we see and encounter. And the real, material world; that was the shadows, mere imprints of The Forms that we experienced as physical phenomena. We as people have the ability to, unlike the prisoners, elevate ourselves beyond the physical world and try to understand the philosophical world, the level of reality where we can comprehend what causes things, what things mean, what their consequences are; where we can explore with an analytical mind and understand our world better on a fundamental level. Or, we can choose not to, and stay looking at shadows and dismissing those willing to think higher.

The Prisoner’s Dilemma

It’s a classic thought experiment, mathematical problem and a cause of much philosophical debate. Over the years it has found its way into every sphere of existence from serious lecturing to game shows to, on numerous occasions, real life. It has been argued as being the basis for all religion, and its place in our society. And to think that it, in its purest form, is nothing more than a story about two men in a jail- the prisoner’s dilemma.

The classic example of the dilemma goes roughly as follows; two convicts suspected of a crime are kept in single custody, separated from one another and unable to converse. Both are in fact guilty of the crime, but the police only have evidence to convict them for a small charge, worth a few months in jail if neither of them confess (the ‘cooperation’ option). However, if they ‘rat out’ on their partner, they should be able to get themselves charged with only a minor offence for complicity, worth a small fine, whilst their partner will get a couple of years behind bars. But, if both tell on one another, revealing their partnership in the crime, both can expect a sentence of around a year.

The puzzle comes under the title (in mathematics) of game theory, and was first formally quantified in the 1950s, although the vague principle was understood for years before that. The real interest of the puzzle comes in the strange self-conflicting logic of the situation; in all cases, the prisoner gets a reduced punishment if they rat out on their partner (a fine versus a prison sentence if their partner doesn’t tell on them, and one year rather than two if they do), but the consequence for both following the ‘logical’ path is a worse punishment if neither of them did. Basically, if one of them is a dick then they win, but if both of them are dicks then they both lose.

The basic principle of this can be applied to hundreds of situations; the current debate concerning climate change is one example. Climate change is a Bad Thing that looks set to cause untold trillions of dollars in damage over the coming years, and nobody actively wants to screw over the environment; however, solving the problem now is very expensive for any country, and everyone wants it to be somebody else’s problem. Therefore, the ‘cooperate’ situation is for everyone to introduce expensive measures to combat climate change, but the ‘being a dick’ situation is to let everyone else do that whilst you don’t bother and reap the benefits of both the mostly being fixed environment, and the relative economic boom you are experiencing whilst all the business rushes to invest in a country with less taxes being demanded. However, what we are stuck with now is the ‘everyone being a dick’ scenario where nobody wants to make a massive investment in sustainable energy and such for fear of nobody else doing it, and look what it’s doing to the planet.

But I digress; the point is that it is the logical ‘best’ thing to take the ‘cooperate’ option, but that it seems to make logical sense not to do so, and 90% of the moral and religious arguments made over the past couple of millennia can be reduced down to trying to make people pick the ‘cooperate’ option in all situations. That they don’t can be clearly evidenced by the fact that we still need armies for defensive purposes (it would be cheaper for us not to, but we can’t risk the consequences of someone raising an army to royally screw everyone over) and the ‘mutually assured destruction’ situation that developed between the American and Soviet nuclear arsenals during the Cold War.

Part of the problem with the prisoner’s dilemma situation concerns what is also called the ‘iterative prisoner’s dilemma’- aka, when the situation gets repeated over and over again. The reason this becomes a problem is because people can quickly learn what kind of behaviour you are likely to adopt, meaning that if you constantly take the ‘nice’ option people will learn that you can be easily be beaten by repeatedly taking the ‘arsehole’ option, meaning that the ‘cooperate’ option becomes the less attractive, logical one (even if it is the nice option). All this changes, however, if you then find yourself able to retaliate, making the whole business turn back into the giant pissing contest of ‘dick on the other guy’ we were trying to avoid. A huge amount of research and experimentation has been done into the ‘best’ strategy for an iterative prisoner’s dilemma, and they have found that a broadly ‘nice’, non-envious strategy, able to retaliate against an aggressive opponent but quick to forgive, is most usually the best; but since, in the real world, each successive policy change takes a large amount of resources, this is frequently difficult to implement. It is also a lot harder to model ‘successful’ strategies in continuous, rather than discrete, iterative prisoner’s dilemmas (is it dilemmas, or dilemmae?), such as feature most regularly in the real world.

To many, the prisoner’s dilemma is a somewhat depressing prospect. Present in almost all walks of life, there are countless examples of people picking the options that seem logical but work out negatively in the long run, simply because they haven’t realised the game theory of the situation. It is a puzzle that appears to show the logical benefit of selfishness, whilst simultaneously demonstrating its destructiveness and thus human nature’s natural predisposition to pursuing the ‘destructive’ option. But to me, it’s quite a comforting idea; not only does it show that ‘logic’ is not always as straightforward as it seems, justifying the fact that one viewpoint that seems blatantly, logically obvious to one person may not be the definitive correct one, but it also reveals to us the mathematics of kindness, and that the best way to play a game is the nice way.

Oh, and for a possibly unique, eminently successful and undoubtedly hilarious solution to the prisoner’s dilemma, I refer you here. It’s not a general solution, but it’s still a pretty cool one ūüôā

“If I die before I wake…”

…which I might well do when this post hits the internet, then I hope somebody will at least look down upon my soul & life’s work favourably. Today, I am going to be dealing with the internet’s least favourite topic, an idea whose adherence will get you first derided and later inundated with offers to go and be slaughtered in one’s bed, a subject that should be taboo for any blogger looking to not infuriate everybody; that of religion.

I am not a religious person; despite a nominally Anglican upbringing my formative years found most of my Sundays occupied on the rugby pitch, whilst a deep interest in science tended to form the foundations of my world beliefs- I think (sometimes) to some personal detriment. This is a pattern I see regularly among those people I find as company (which may or may not say something about my choice of friends)- predominantly atheists with little or no religious upbringing who tend to steer clear of religion and its various associated features wherever possible. However, where I find I differ from them tends to be when the subject is broached when in the present of a devoutly Christian friend of mine; whilst I tend to leave his beliefs to himself and try not to spark an argument, many others I know see a demonstration of his beliefs as a cue to start on a campaign of ‘ha ha isn’t your world¬†philosophy¬†stupid’, and so on. ¬†I tend to find these attacks more baffling and a little saddening than anything else, so I thought that I might take this opportunity to take my usual approach and try to analyse the issue

First up is a fact that most people are aware of even if it hasn’t quite made the jump into an articulate thought yet; that every religion is in fact two separate parts. The first of these can be dubbed the ‘faith’ aspect; the stories, the gods, the code of morals & general life guidelines and such, all of the bits that form the core of a system of beliefs and are, to a theist, the ‘godly’ part of their religion. The second can be labelled the ‘church’ aspect; this is the more man-made, even artificial, aspect of the religious system, and covers the system of priesthood (or equivalent) for each religion, their holy buildings, the religious leaders and even people’s personal interpretation of the ‘faith’ aspect. Holy books, such as the Bible or Torah, fall somewhere in between (Muslims believe, for example, that the Qur’an is literally the word of Allah, translated through the prophet Muhammed) as do the various prayers and religious music. In Buddhism, these two aspects are known as the Dharma (teachings) and Sangha (community), and together with Buddha form the ‘three jewels’ of their religion. In some religions, such as Scientology (if that can technically be called a religion) the two aspects are so closely entwined so as to be hard to separate, but they are still distinct aspects that should be treated separately. The ‘faith’ aspect of religion is, in most respects, the really important one, for it is this that actually formulates the basis of a religion; without a belief system, a church is nothing more than a place where people go to shout their views at those who inexplicably turn up. A religion’s ‘church’ aspect is its organised divisions, and exists for no greater or lesser purpose than to spread, cherish, protect and correctly translate the word of God, or other parts of the ‘faith’ aspect generally. This distinction is vital when we consider how great a difference there can be between what somebody believes and what another does in the same name.

For example, consider the ultra-fundamentalist Taliban currently fighting their Jihad (the word does not, on an unrelated note, technically translate as ‘holy war’ and the two should not be thought of a synonymous) in Afghanistan against the USA and other western powers. Their personal interpretation of the Qur’an and the teachings of Islam (their ‘church’ aspect) has lead them to believe that women do not deserve equal rights to men, that the western powers are ‘infidels’ who should be purged from the world, and that they must use force and military intervention against them to defend Islam from said infidels- hence why they are currently fighting a massive war that is getting huge amounts of innocent civilians killed and destroying their faith’s credibility. By contrast, there are nearly 2 million Muslims currently living in the UK, the vast majority of whom do not interpret their religion in the same way and are not currently blowing up many buildings- and yet they still identify as Islamic and believe in, broadly speaking, the same faith. To pick a perhaps more ‘real world’ example, I’m sure that the majority of Britain’s Catholic population steadfastly disagree with the paedophilia practiced by some of their Church’s priests, and that a certain proportion also disagree with the Pope’s views on the rights of homosexuals; and yet, they are still just as Christian as their priests, are devout believers in the teachings of God & Jesus and try to follow them as best as they can.

This I feel, is the nub of the matter; that one can be simultaneously a¬†practising¬†Christian, Muslim, Jew or whatever else and still be a normal human being. Just because your vicar holds one view, doesn’t mean you hold the same, and just because some people choose to base their entire life around their faith does not mean that a person must be defined by their belief system. And, returning to the subject of the ridicule many¬†practising¬†theists suffer, just because the ‘church’ aspect of a religion does something silly, doesn’t mean all practitioners of it deserve to be tarred with the same brush- or that their view on the world should even matter to you as you enjoy life in your own way (unless of course their belief actively impedes you in some way).

I feel like I haven’t really got my point across properly, so I’ll leave you with a few¬†links that I think illustrate quite well what I’m trying to get at. I only hope that it will help others find a little more tolerance towards those who have found a religious path.

And sorry for this post being rather… weird

The Chinese Room

Today marks the start of another attempt at a multi-part set of posts- the last lot were about economics (a subject I know nothing about), and this one will be about computers (a subject I know none of the details about). Specifically, over the next… however long it takes, I will be taking a look at the subject of artificial intelligence- AI.

There have been a long series of documentaries on the subject of robots, supercomputers and artificial intelligence in recent years, because it is a subject which seems to be in the paradoxical state of continually advancing at a frenetic rate, and simultaneously finding itself getting further and further away from the dream of ‘true’¬†artificial¬†intelligence which, as we begin to understand more and more about psychology, neuroscience and robotics, becomes steadily more complicated and difficult to obtain. I could spend a thousand posts on the subject of all the details if I so wished, because it is also one of the fastest-developing regions of engineering on the planet, but that would just bore me and be increasingly¬†repetitive¬†for anyone who ends up reading this blog.

I want to begin, therefore, by asking a few questions about the very nature of artificial intelligence, and indeed the subject of intelligence itself, beginning with a philosophical problem that, when I heard about it on TV a few nights ago, was very intriguing to me- the Chinese Room.

Imagine a room containing only a table, a chair, a pen, a heap of paper slips, and a large book. The door to the room has a small opening in it, rather like a letterbox, allowing messages to be passed in or out. The book contains a long list of phrases written in Chinese, and (below them) the appropriate responses (also in Chinese characters). Imagine we take a non-Chinese speaker, and place him inside the room, and then take a fluent Chinese speaker and put them outside. They write a phrase or question (in Chinese) on some paper, and pass it through the letterbox to the other person inside the room. They have no idea what this message means, but by using the book they can identify the phrase, write the appropriate response to it, and pass it back through the letterbox. This process can be repeated multiple times, until a conversation begins to flow- the difference being that only one of the participants in the conversation actually knows what it’s about.

This experiment is a direct challenge to the somewhat crude test first proposed by mathematical genius and codebreaker Alan Turing in the 1940’s, to test whether a computer could be considered a truly intelligent being. The Turing test postulates that if a computer were ever able to conduct a conversation with a human so well that the human in question would have no idea that they were not talking to another human, but rather to a machine, then it could be considered to be intelligent.

The Chinese Room problem questions this idea, and as it does so, raises a fundamental question about whether a machine such as a computer can ever truly be called intelligent, or to possess intelligence. The point of the idea is to demonstrate that it is perfectly possible to appear to be intelligent, by conducting a normal conversation with someone, whilst simultaneously having no understanding whatsoever of the situation at hand. Thus, while a machine programmed with the correct response to any eventuality could converse completely naturally, and appear perfectly human, it would have no real conciousness. It would not be truly intelligent, it would merely be just running an algorithm, obeying the orders of the instructions in its electronic brain, working simply from the intelligence of the person who programmed in its orders. So, does this constitute intelligence, or is a conciousness necessary for something to be deemed intelligent?

This really boils down to a question of opinion- if something acts like it’s intelligent and is intelligent for all functional purposes, does that make it intelligent? Does it matter that it can’t really comprehend it’s own intelligence? John Searle, who first thought of the Chinese Room in the 1980’s, called the philosophical positions on this ‘strong AI’ and ‘weak AI’. Strong AI basically suggest that functional intelligence is intelligence to all intents and purposes- weak AI argues that the lack of true intelligence renders even the most advanced and realistic computer nothing more than a dumb machine.

However, Searle also proposes a very interesting idea that is prone to yet more philosophical debate- that our brains are mere machines in exactly the same way as computers are- the mechanics of the brain, deep in the unexplored depths of the fundamentals of neuroscience, are just machines that tick over and perform tasks in the same way as AI does- and that there is some completely different and non-computational mechanism that gives rise to our mind and conciousness.

But what if there is no such mechanism? What if the rise of a conciousness is merely the result of all the computational processes going on in our brain- what if conciousness is nothing more than a computational process itself, designed to give our brains a way of joining the dots and processing more efficiently. This is a quite frightening thought- that we could, in theory, be only restrained into not giving a computer a conciousness because we haven’t written the proper code yet. This is one of the biggest unanswered questions of modern science- what exactly is our mind, and what causes it.

To fully expand upon this particular argument would take time and knowledge that I don’t have in equal measure, so instead I will just leave that last question for you to ponder over- what is the difference between the box displaying these words for you right now, and the fleshy lump that’s telling you what they mean.