In the beginning let us repeat the question we already know, because this question will be really helpful to define stupidity:
Where does stupidity come from?
Let us repeat also the answer, because this answer will help us a lot, too:
From everywhere and from nowhere.
Stupidity does not come from. Stupidity is. It simply is. Stupidity permeates the entire world. Stupidity is the soul of the world. Its spirit and mind. The world is stupid, just stupid. That's all.
Let's repeat another question: why the world is stupid, if it could be wise? And, could it really be wise, because if it is stupid, maybe it can not be wise and that is why it is stupid... Yes. All the time we ponder whether the world is stupid or wise. All the time only stupid or wise. Are there any intermediate states? Is there anything between stupidity and wisdom? Could the world be a little wise and a little stupid, and neutral in between – because if stupidity and wisdom are extreme states, as if two ends of a stick, then something that is between these ends, it means a stick, may be neutral. Or maybe the world is one third wise and two thirds stupid. Or fifty-fifty. Wise-stupid. Stupid-wise. Or wisely stupid. And stupidly wise.... Is this the same or not?
No matter how stupid these questions may seem, we don't have to be ashamed of asking them and we will ask one more, namely: has the world always been stupid, or maybe not always? If not always, it means it got stupid one day – this could happen in one very moment, but this could happen gradually, slowly, systematically, regularly or irregularly, crawling or jumping. It seems the making of the world was something stupid, a first act of stupidity. Not necessarily this very first act of stupidity resulted in the stupid world. Not necessarily. This is not so obvious. A lot of wise acts get stupid results – so it might be that stupid acts can result in something wise. Stupidity is unpredictable, this is well known. It would be stupid, if stupidity created wise world, and if it was stupid, then it might happen so. Really, it might.
Is the world really stupid, or only mad?
Madness is not only madness. Sometimes it is a method. However madness is not identical to stupidity. No, it is not. Madness is quite bizarre state: sometimes it dangerously approaches unbridled rage, savagery, destructive and demonic, sometimes it is just too much fantasy, temporary lack of common sense. The madness which is a method, is a result of conscious choice, while the conscious choice of sophisticated strategy of acting speaks rather in favour of wisdom.
But not only madness can be a method. Pretending a fool also can be an effective strategy. This makes our situation much more complicated. If it turns out the world is not stupid at all, but it only pretends to be stupid, what will we do?
What will we do then?
And now?
Now we must define what stupidity is. Without that we can't go any further. We will get to nowhere. We will run on the treadmill.
If stupidity is the opposite of wisdom, this means stupidity is non-wisdom.
Then wisdom is non-stupidity.
If so, then somebody who is not stupid should be wise, while somebody who is not wise should be stupid.
However it is not so. The fact that somebody is not stupid does not mean, that somebody is wise. Also the fact that somebody is not wise does not mean at once that somebody is stupid. It can happen, not really seldom, that somebody wise can do something stupid, can get stupid for a while, or simply is stupid within certain area. It can also happen, though rather seldom, that somebody stupid will do something wise, or get wise for a moment, or is wise within certain areas, or at least not stupid. These facts tell us that stupidity is not simple non-wisdom, like wisdom is not simple non-stupidity.
This is so, because stupidity is complex. It is something very complex. It consists of several elements – we don't know of how many. This is why there is and there can be no simple definition of stupidity which would explain clearly what it is. We said “something complex”. “Something” - but what? Is this something a phenomenon? State? Thing? Process? Sort of space? Kind of time? A bit of everything?
The last proposition seems the most sensible. If a bit of everything, then it is also sensible to speak about a mosaic structure of stupidity. More, in each case this mosaic is different. There are no two mosaics that look exactly the same. Well, theoretically it is possible, of course, but practically it is almost impossible. Like almost impossible, practically impossible, is to find two persons who would know exactly the same and would not know exactly the same, although theoretically it is possible and easy.
Maybe it would be easier to define wisdom. And if so, would this be of any use for us? If stupidity is not a simple opposite, nor contradiction of wisdom, then a definition of wisdom is of very little use for us. For example knowledge. Knowledge can be an ingredient, an element, a part of both wisdom and stupidity. The difference is that knowledge seems to be necessary for wisdom (it's hard to imagine a wise human who knows nothing, though the man who is supposed to be the wisest used to declare that he knew nothing, but he did so deeply concerned by his limited knowledge in comparison to his unlimited ignorance – a stupid human does not give a damn to such problems), while it is indifferent for stupidity. There are humans who have great knowledge and don't know how they can use it, so they are not wiser than an ordinary fool. So, it's not like that stupidity is related only to ignorance, to non-knowledge, while wisdom is related to knowledge only.
So, we already know, that knowledge is one of the ingredients of stupidity. Neither ignorance, nor non-knowledge, but knowledge. Bear it in your minds, ignorance or non-knowledge is not possible. It means, non-knowledge is possible, of course it is, yet somebody or something that knows absolutely nothing can not exist, will perish at once. If somebody or something that knows nothing can not live, or can not exist, then non-knowledge, or knowing nothing (which is, of course, not the same), does not exist, either, at least practically. To exist one needs to possess a minimal quantity of knowledge, a non-zero, above-zero, knowledge. Could a sub-zero, a negative, knowledge exist? What a fantastic question!
Does a sub-zero knowledge exist?
With no doubt there is a secret knowledge, but this is something else. A secret knowledge is a knowledge which should be known only be the initiates, but is known by everybody. The division of knowledge into theoretical and practical, or verbal (verbalized) and non-verbal is much more interesting for us. Let's imagine a musician who can play really marvelously, but can say nothing about what and how he plays, because he doesn't know names of keys and tones, maybe even doesn't know what a key is. And the opposite: somebody who can analyse the entire composition (tune) perfectly, name even the most insignificant and unnoticeable elements of this composition (tune), but can't play it. Which one of them knows more about music? Or: which one of them is wiser? which one of them is more stupid?
To know how to use knowledge is as important element as the knowledge itself. Knowledge is like a pile of bricks. We must know to build something using these bricks. Using the same bricks different houses can be built. Some of them are being built wrong from the very beginning, they collapse, and if sometimes they don't this is against any logic. Some of these houses are built properly, but they look awfully and it's hard to live in them, because they are not functional. There are houses which have been built well, look good, are functional, it's nice to live in them, though with no doubt some of us would not like them and would not like to live in them and would maintain it is impossible to live in them. As usually there are different variants, and great number of variants does not help us – it only makes us more convinced we are right supposing stupidity has a complex structure.
Is the ability, the skill, to use knowledge the same as the ability, the skill, to think logically? Partially yes. Or partially no. Finding among galore of information gathered in one's head those which are needed in this very moment belongs to the skill of using our knowledge. However this can hardly be qualified as logical thinking – our knowledge doesn't have to be stored logically, chaos is not really worse than order, and if we are used to chaos, it can be even better. Logical thinking is, to great extent, the skill to connect properly causes with effects. If we master this skill, we will be able to ask sensible questions and give sensible answers. We will be able to observe and notice what we should notice, not what we would like to notice... But these are less important elements, kind of sub-elements, and we won't focus on them now. Maybe sometime later.
Not many elements we have.
Yes, not many.
A few, indeed.
But they seem basic. Fundamental. The mournful edifice of stupidity is rising on them.
And how about mimicry? The stupidity which perfectly pretends wisdom?
And how about nonsense? To occupy oneself with something that has no sense at all, what seems to have sense and we give to it time and energy, but in fact it is senseless. At least in a limited, narrow context – because in larger context it may have sense. Stupid words can be composed into wise text. While a stupid text can consist of wise words. Can nonsense, senseless, words create a senseful, sensible text? A nonsense text can be composed of sensible words, no doubt.
Anything else?
Anything more?
Aim?
Fire!

Well, well, the conclusion is not merry. But it is not sad, either. It's very difficult to define stupidity. Very difficult does not mean it's impossible. Very difficult means very difficult. Very not easy. Stupidity has extremely rich history. Stupidity is omnipresent. Yet we know so little about it. This is not surprising. Stupidity is elusive and intangible and imperceptible like an air. Swampy and marshy. Amorphous like a fog. We could multiply epithets, attributes, adjectives, metaphors almost endlessly – almost, for the limits of our imagination would be the end of this list.
If stupidity is so difficult to be defined, almost touches indefinability, we should try to define it through indicating. Nothing special this would be. There are many phenomena, states and processes which we try to define as stubbornly as inefficiently, to imprison them in a word formula, which is only next manifestation of our stupidity, though sophistication and exquisiteness of these formulas seem a manifestation of our profound wisdom. Attempts to describe these phenomena, states and processes (for example composing of a music) are as nonsense as attempts to take off while running and swinging arms, but they won't be considered manifestation of stupidity while running and hand fluttering will. Nobody learns music reading about music, but takes an instrument and starts to play, practises and listens the others play. And the others show: play in this way, or in that way. And they play. He listens and observes carefully, then tries to play like they play. Or not like them, if he didn't like the way they were playing.
Indicating will be difficult, too. What is stupid for us, is wise for them. And vice versa. We are listening in radio to a conversation with a politician. Doesn't matter if he is from the left or from the right side of the political scene. He is well known, he speaks fast and a lot – this is what does matter. He's speaking so fast and about so many things that he does not control what he's speaking about. Every now and then he contradicts himself, mixes tenses and modes, mixes threads, jumps from one idea to another as if a mad switch-man worked in his head, whose biggest passion was to cause as many train collisions as possible. Chaos and gibberish. The bigger chaos the better. After a dozen of minutes the journalist gives up, she stops repeating stubbornly a question because she knows there is no chance to get an answer even slightly referring to the problem. The politician keeps gibbering with incredible zest... Let's summarize. We could record this gibbering then indicate it and say: this is a stupid talk, this is how a stupid talk looks like. We could also indicate the politician himself and say: this is a stupid politician. Or more generally: this is a fool, this is a man who loves stupidity. But we must show the respect to this fool. He chose a strategy (did he? rather not – it looks like he had no choice) and this strategy worked fine, really fine. Even if he didn't make a choice, because he had no choice, he used a wise strategy. He won the battle. Absolutely and with no doubt. Stupid gibbering turned out to be wise gibbering, the strategy was wise enough to win the battle, or at least not to be defeated.
Stupidity is not so stupid as it looks like.
Stupidity has its own wisdom.