A brief history of melancholy - Courtney Stephens

View full lesson: ed.ted.com/lessons/why-do-some...
If you are a living, breathing human being, chances are you have felt sad at least a few times in your life. But what exactly is melancholy, and what (if anything) should we do about it? Courtney Stephens details our still-evolving understanding of sadness -- and even makes a case for its usefulness.
Lesson by Courtney Stephens, animation by Sharon Colman Graham.

[@XtremeKaiba]

I do have depression and sometimes it does inspire more creativity in me than when I am happy.

[@JustNatax3]

XtremeKaiba As a manic depressive person it's the other way around. When I'm in a depressive episode I can't do anything. Emotional numbness kills every creativity in me and I even struggle with the easiest tasks like moving and keeping my eyes open. Whenever I'm euphoric I start hundreds of projects I'm never able to finish, I'm totally out of my mind and think ten steps ahead, overflowing with creativity.

[@XtremeKaiba]

I write poetry when I'm sad

[@operatorjewski9450]

If you are really depressed i dont think you have said this,i think your just sad.

[@operatorjewski9450]

Being sad is a normal thing.

[@fluffypancakes899]

Nati Whatever i agree. My depressive episodes makes it hard for me to fullfill even the the most mundane activities. House chores seem like a huge task and merely getting up in bed takes willpower (i am not exaggerating). However, when i am on my "good days" i am struck with a burst of energy and motivation and i am suddenly overwhelmed with drive to do and do and do anything and everything i can think of. So much that my body cannot keep up with my mind and i will get frustrated as i cannot execute my thoughts the way i pictured them. Hence, i cannot finish anything i've started. I'm not productive both ways. It is so frustrating.

[@walkingphrase]

Melancholy might be uncomfortable, but I wouldn't want to trade it for any paradise engineered environment or medication. I kind of agree with poets and philosophers that melancholy can be a good experience and is sometimes necessary. Depression, on the other hand, is a totally different issue.

[@zbynekdrab8077]

No it isn't, the two are different historical terms for the same thing.

[@Torakashi]

@@zbynekdrab8077 They are definitely different. They sometimes get mixed up. But while melancholy can be quite a colorful and emotional state, depression is the absence of emotion. At least that is my understanding.

[@bussydestroyer5602]

Zbynek Drab idk if you still think this way 5 years later but there is definitely a dichotomy between these 2 terms in the modern day in psychology and medicine, history doesn’t matter.

[@petrichor9600]

@@zbynekdrab8077 for me though it's different as well. i've experienced both and one thing i noticed is that in depression i feel as if i don't want to do things that i used to love, but in melancholy it's kind of like you're sad, but that just makes you more observant and appreciative of the world around you, therefore feeling more creative.

[@joseylastborn8790]

@@petrichor9600 The evolutionary h e u r i s t i c is underapplied what causes something like addiction the results in depression is of course the appeals of melancholy. Depression is an evolved response to Winter and seeking Melancholy can trigger this hibernating state. Cardiac activity social activity good amounts of sunlight are now encouraged for those whose job is to learn and to think. When I have carriage for family who have been at risk I have appreciated the value also evolutionary of being able to think and to remember the past and to integrate memories obtaining insight. Where I to do it again I would push even harder in the early stages for more cardiovascular activity and son light exposure. During this 10 year of final Chapter caregiving I was able to incorporate modern high intensity high quality lighting but again addiction must be policed against and often would encounter my loved one abusing the solid-state vanity lights never using the dimmer. Smart dimmers can allow you to increase the brightness of your built environment during appropriate times of the day but only people that are not at risk should be able to override those schedules. In our jails we have put high intensity lighting that is often not utilized because the staff wants to kind of sleep walk during the day because they're up all night watching Netflix at home. This causes the inmates to go into the depression that was understood by the architect so it's not just keeping the lights down during the evening but it's keeping them up during the day the Corrections Officers must be locked out of disabling. Hibernation is likely what have allowed our brains to get so big essentially it's a seasonal return to the neuronal development that precedes are being born. This is why people who have been on adderal or other antidepressants will often have the maturity of an infant.

[@MiotaLee]

Melancholy is a wonderful state of mind. It's the absence of happiness but lacks the sting of sadness which allows, at least me personally, to be more creative.

[@emiliadragulin5826]

Yeah. To me it really is, like when i'm happy i don't have any idea of what to draw. But when i'm sad all i want to do is paint all my feelings down

[@theedamz5750]

true

[@touboulayefaobuda7198]

You are wrong

[@wecanthandletruths]

I too am a more creative person because of this. My strenghs to truly feel. My empathic ability is enhanced. My ID my ego is non-existent. There is a feeling of peace. I prefer my own company most of the time. ✌ ❤

[@meltcy]

I love the way you expressed that!

[@kryldon8146]

I really want them to make a video about nostalgia

[@ruoweilim7334]

yes!

[@alishad.5260]

Well im from the future and they did yay

[@crossfitjohnathan9032]

That's a good idea

[@trantrantoo]

Say no more fam.

[@sophiebai5540]

i want that too

[@j.s.1816]

In much of today's world, sharing sadness sadly doesn't lead to bonding. People are too busy to do more than give cliché responses.

[@drz616]

Exactly.

[@babyraose]

someone noticed

[@jappleton0901]

Jen S. Well said...

[@Ablequerq]

Or they use it against you.

[@qwenm824]

Since people work a lot more now and social media paralyze them with sad news every day, a good laugh is preferred

[@darthkate7449]

Thinking the way Emily Dickinson did made me postpone looking for help for my overwhelming feeling of melancholy. When I crossed the line and was talked into going to a psychiatrist, he asked me: "Why have you waited this long?". I answered: "People have hurt more than I have, who am I to complain about my pain?". I have since learned: Sorrow has no measurement, and shouldn't be taken so lightly.

[@babartahir9004]

Did it help??

[@darthkate7449]

Babar Tahir A bit, but at least I'm not shy or afraid to ask for help. And that's one step closer to leading a happier life :)

[@Axkarshan]

imagine how itd feel to be a 'dickinson' in 2022 💀

[@kairuzperez833]

It is both a blessing and a curse to feel everything so deeply

[@brave.9560]

I think the strongest melancholy I’ve ever felt was right after a concert. Feeling incredibly sad that it’s over, but at the same time also extremely euphoric.

[@itstitli1585]

"If you never felt melancholy, you've missed out on part of what it means to be human "❤️

[@joukokulhelm6844]

If i could trade my melancholy for not knowing everything about human experience, i wouldent even plink....

[@curlyprivat22]

I'm perciving melancholy as a beutiful feeling. I normally get it - not exclusive - when I celebrate with my friends. That feeling, that sting, that all will end, shows me the beauty of the moment.

[@ahundredbroken4644]

Cookie Ann Yeah.. I with you.

[@user-cx6ir4zm9r]

Ahundred Broken melancholy of haruhi suzumiya

[@jenny_coolbeans3016]

Cookie Ann me too

[@sadias.4596]

This is so true. Cookie Ann.

[@sadias.4596]

This is so true. Cookie Ann.

[@gracet6533]

when I was young and filled with folly, I fell in love with melancholy Edgar Allen poe

[@michaelsmithson6533]

“If life was always sunny, it would be a desert”

[@mdnd8]

this is such an underrated comment

[@whyar3y0uga34]

MF DOOM??

[@theowlfromduolingo7982]

@@whyar3y0uga34 whaaaaat?

[@brandonb3273]

If it always rained, earth would be an ocean.

[@coachrongetitdone]

King Solomon wrote "For with much wisdom comes much sorrow. " Ecclesiastes 1

[@charmedprince]

Ignorance, truly, is bliss. . .

[@Hosni_Dubu]

coachrongetitdone yeah right, one of my favorite quotes from the book of Ecclesiastes...They should have just quoted Solomon lol

[@rebeccap6878]

@@charmedprince in a sense. But how much you would miss out....

[@bigworlds647]

I would argue that melancholy is more of an "inside one's mind thing", rather than something fundamentally social. It is associated with wisdom mostly because it is the time in our life when we seek solitude and try to figure things out ourselves, often trying to reason outside of the thinking scheme imposed on us by the society.

[@WWS322]

I was an extraordinarily happy child who had never known any sadness. I can remember feeling a little bad from family arguments, mostly powerlessness. But I never knew true emotional pain until I got schizophrenia. Sorrow is the word I like to use, the worst pain there is, loneliness we all feel. I can go from thinking I feel nothing to a great sadness that seems like there's nothing good in it at all.

[@Burcakmusic]

I hope you feel better Justin ❤️

[@kaganuni]

1:48 R.I.P. physics

[@a_cc4954]

thats how physics works

[@PutuDharmaMahaYusa]

you miss the point of the video

[@user-vx8qt9cd8o]

***** Nobody said the car don't have motor, if you have motor not powerful enough, you can gain inertia that will help you climb.

[@megayamesh]

it's not video about physics

[@capitaopacoca8454]

It seems that people from 6 years ago couldn't understand a joke.

[@ese_cholito]

Sadness overall is interesting, when meditating, I try not to forget but to let it pass. I think on these issues and I come up with some quick solutions once I get passed the sadness part of those moments. When I play piano when I'm sad I feel like I made a breakthrough in my music, even if it's a small tone change. Sadness can be useful if you keep your mind steady.

[@zakariaali5241]

I agree I use sadness as a tool to push me harder in the gym and in the morning thinking if my enemies or dad saw me he would say you know better now do better

[@nataliexbreakdown]

the part about language influencing how people feel is so interesting!!

[@Kta8548i]

Arrival

[@neemmol7734]

I have this feeling where I am constantly sad and the way I cure this is by releasing my emotions alone, by spending time alone and reflecting on myself. I sometimes cry while staring at sunsets. And in this way i find peace and calmness

[@lilaztec416]

I feel melancholic and a sort of chronic sadness. The word Melancholia was the main thing that inspired my latest album “Melancholy”

[@percocetpudding]

I thank my deepest sorrows, they have given me the kind of wisdom to help others

[@AppallingScholar]

I grieved sadness and loneliness but they made me understand the true flavours of happiness and love

[@crazylazyable]

After experiencing a great opera, or a tragic stageplay, I can get very melancholic. And I love it! It is good to feel like that sometimes, and I wouldn`t like to see a world without it.

[@ZenDragonYoutubeChannel]

The subject of human sadness is more interesting than that of human baldness, but isn't the title and description of this video wrong, or am I missing something?

[@redkings6976]

Zen-Dragon I don't get it... they seem pretty normal to me? Was it different two years ago??

[@jolinzeng]

You're awesomeness allowed you to criticize this video funnily

[@Anarcath]

Those of us who suffered know that we can live without it.

[@MS-gv6jd]

i like how he explains and connects with poets and poems

[@marcusblacknell-andrews1783]

This is perfect for my gothic poetry.

[@sophiamariego8942]

a'right i've been experiencing how it feels to be a human for years, give me happiness now

[@bloodyrose1995]

Without sadness there can be no understanding or full appreciation of other emotions. Art would also be cut down completely... along with human interaction and connections. Sadness is a part of life.

[@mattsbs7464]

bloodyrose1995 Go watch CGP Grey's video: Why die? He talks about that and safe to say he does not agree with you.

[@mcslammer4989]

+Matt SBS no right or wrong answer here

[@user-ge5yy6zx4m]

thank you for being part of my assignment

[@NikiWonoto26]

well, this is actually quite true .. people need to know more & deeper about why "sadness" might be a *good* thing (not always a 'bad' thing) ! :)

[@ernestpatrickzaragoza2702]

2:15 , I would argue that Robert Burton borrowed a verse from the Bible that is found on Ecclesiastes 1:18, as stated "For in much wisdom is much grief: and he that increaseth knowledge increaseth sorrow." Therefore, those words that he wrote on his book "The Anatomy of Melancholy" are not from him but from Solomon :)

[@j.s.1816]

Yes.

[@SoulSoldSeparately]

I would have loved to see an actual differentiation between the meaning of sadness and melancholy after all, as I see it, melancholy is always something more... well... procreative... often I find beauty in melancholy... it is a 'warmer' feeling, even if it weighs so heavy on ones heart there is a reason for ones sadness, grief, pain, sorrow, depression, melancholy, etc... but they are different states of the overall concept of sadness but I really liked the conclusion here... and basically all the TED-Ed videos :)

[@daniashoaib9407]

"Sadness is not only an evitable part but an essential one. If you never felt melancholy you have missed on part of what it means to be a *human* "

[@justjhaycee]

Through melancholy we appreciate the real joy and happiness😊

[@hishouha]

Melancholy makes me more creative, I can see the world as a piece of art through its dark and bright sides. Death and life, happiness and sorrow… they go together no matter what. Yet it’s so easy to fall into despair with that almost constant state of mind

[@kimaki]

That's the most sad and beautiful lesson i've seen here on TED (: nice work, as always

[@bkw11]

of course it has a strong tie to our evolutionary background. notice how when you take action, often, the saddens dissipates, as if sadness is a motivation to take action; a trigger.

[@juuk3103]

"He who increaseth wisdom increaseth sorrow"

[@KennethSaul]

Ecclesiastes 1:18

[@leasingmango1249]

Melancholy is the best feeling, except nostalgia. Put the two together and you get driving on a highway at night in the rain

[@vascomachado2570]

This is perfect

[@painpeace3619]

Living melancholy, is true beauty, u will feel nihilism...

[@nehamathur8522]

This channel is beyond fantastic!

[@honeynfred]

Just about all creative people feel depression it is often a trigger which has led to the most beautiful art, music and stories.

[@JustNatax3]

Emily Dickinsons poems always make me melancholic.. :(

[@charmedprince]

What about Virginia Woolf?

[@setsail.5269]

One of the best TedEd videos I've seen. Thanks a lot for puting in the work to make this. :)

[@diegomunoz6225]

Gotta love the physics of that rollercoaster assent.

[@sketchyvideos3261]

It makes sense to me that melancholy is necessary in gaining wisdom. Experiencing pain is one thing, it helps us to learn from our mistakes, so as not to experience it again. But when experiencing true melancholy, it can allow you more time to truly think over and come to understand the situation. Like if you understand too.

[@lucaslayton3974]

From an evolutionary point of view, sadness helps us identify situations that are bad for us as individuals and as a group, so we know that we should try to avoid those situations. E.g. the loss of someone/something makes us weaker as a whole. And it also makes us sad. Pain and weakens us, and it makes us sad, not only for ourselves but also for others (empathy).

[@muthukumaranl]

Beautifully made...and informative....can't think TED-Ed enough...

[@eb3289]

This is the best thing I've ever heard, my mind changed

[@smashedpasta]

Amazing video, amazing explanation, and I’m fond of the music! You never fail us!

[@LisaS1]

I've always suffered from sadness and depression; it's worse now then it's ever been - I can thank my siblings and related family members for allot of it.

[@VarshaManoj]

Loved the video...I find melancholy to be a beautiful experience. It's like a time freeze for me, which helps me to be as creative as possible.

[@sumaiyakalim7420]

Lets just admire the wonderful video they made, too much of creativity i salute you!

[@ayceinquisitor190]

"Paradise Engineering" is destructive cowardice. ALL emotions are essential to experience and understand within ourselves. We form bonds over sadness because we can empathize with suffering and pain, and together build ways to better manage those emotions. Do not run away from them, because if you do not get through to the other side of it, it will bottle and fester, and eventually start harming your ability to function, and then it gets a lot harder to actually do.

[@cutri2219]

Melancholy makes me appreciate more the people around me. When im melancholic i feel in a eternal sunday night.

[@booh12469]

Excellent. As usual with Ted-Ed, the quirky animation ensures focused listening. Dualism: striving towards a balanced dynamic.

[@xfrancesco10x]

Wow.. That was a beautiful one!

[@YtubeUserr]

The title and content are not consistent?

[@wesleyhempoli5548]

+Olecarnivorous I guess you didn't read the description because that makes the least sense of all

[@DaveDeRoseMusic]

+wesley Hempoli hahaha... wow that is brilliant

[@RashnaManero]

Muchas gracias, me encantó como esta tratado. Lo comparto con gusto.

[@LittleMissJellybeann]

Great and informative as usual, keep it up guys!

[@iamyouu]

This video is awesome thanks for making and sharing it.

[@Melissa-ek7dw]

Melancholy is something you get when you understand that no one is perfect fit for you else you

[@TheSpecialJ11]

Ummm...the description doesn't seem the same, although I'm sure a correlation can be struck here. Baldness and sadness are probably tied.

[@mrsCrab961]

maybe sadness is the real reason for baldness. or baldness leads to sadness? nobody knows.

[@cazwalt9013]

A human without sadness is not a human it teaches us a lot

[@TheForsakedAngel]

A World without sadness is the worse idea of all... If everything is good for us then it stops being good and just becomes normal... We need sadness so that we can feel joy... There has to be a balance...

[@DavidPearce]

Jorge Daniel, intuitively you're right. But compare people today who endure chronic depression. Would we tell them "If everything is bad then it stops being bad and just becomes normal"? Life can be animated either by information-sensitive gradients of misery, information-sensitive gradients of bliss, or some mixture of the two. Biotechnology promises the ability to choose the upper and lower bounds of your hedonic range, and also approximate hedonic set-point. Shouldn't we welcome the freedom and opportunity to enrich our quality of life?

[@TheForsakedAngel]

David Pearce You could be right, but let's say fuck you to science and concentrate on the real World, do you think the people that are paid 5000€ a month are happier than the ones who receive 500€? No... They just have more, better stuff, but they are so used to it that for them it's nothing special, it's only normal, and they could have better stuff if they were paid 10000€... And the same goes for those people, and so on and so forth... So no, you can't always be happy, you have to sleep on the floor to learn how to appreciate your mattress...

[@zeynepegekucuk]

I had depression for and I couldn’t care less bout people’s opinions. Now everboby’s opinion constructs my reality of myslef. I don’t mean to support or uplift (is it how it’s written?idk) the idea of being depression but that period of time, my life was freer per mindset and etc

[@Axhar1]

I was reading a book and then i stumble upon this word, i did not know the meaning of it, so i searched it and here i am...more interested in meloncholy than the book i was reading.

[@scp-se3er]

What was the book you read? I'm just curious... would you mind if you give me a brief overview of it? :D

[@gamezoid1234]

This is amazing

[@qrsxo5669]

1:56 "If you've never felt melancholy, you've missed out on part of what it means to be human" 👐

[@qrsxo5669]

So true. !!

[@lauraaura2367]

Beautifully written

[@azuredragonofnether5433]

It essentially means: If you never felt sad, you are a psychopath. It's an exaggeration, I know. But that (not mine) sentence is written better than my essays.

[@sensftrs]

the rollercoaster really got me

[@heididamayoupham182]

Such a beautiful, articulate video. That rollercoaster animation was genius.

[@TheErudite21]

That Paradise Engineering is quite scary... read a Space Opera where there was a race of aliens that never experienced any sort of strife or violence in the history of their memory... they were like a bunch of teenage girls whose most pressing concerns were the most fickle and shallow things...the only way they even functioned as a society were the 'grunts' that basically handled all that nitty gritty parts of society: everything from sewage maintenance to food production to engineering...while the 'peaceful' folk saw them as we do machines or slaves (in an apathetic, non-prejudiced manner)... that plus, its just scary to imagine humans with the power to re-engineer other being's natural states. Just imagine corporations or governments that would make it mandatory to purge you of all sadness, anger, and other strongly negative emotions (of which are actually catalysts of our most productive times). I doubt humanity will let itself create some great utopia though; simply because we humans cannot imagine, grow, or enjoy a world without violence, drama, or some other kind of 'negative' emotions... in fact, boredom will immediately run rampant if such a paradise would come to fruition, and we do the craziest, most brilliant, and stupidest things out of boredom...

[@DavidPearce]

Historian Lewis Namier once remarked how “One would expect people to remember the past and imagine the future, but in fact…they imagine the past and remember the future.” The "future" most of us remember is a blend of childhood science-fiction novels and Hollywood movies. Yes, life based on genetically pre-programmed gradients of bliss might be shallow, but such biohappiness might instead be rich, multi-faceted and profound. Coercive happiness? It's conceviable; the historical record suggests otherwise. Perhaps compare today's biology of involuntary suffering. Would life animated by gradients of intelligent bliss be "boring"? Biotechnology promises to abolish the molecular signature of boredom, making such states impossible. Future life may be driven by information-sensitive gradients of fascination. One again, biotechnology opens a menu of options. Either way, shouldn't we be free to choose?

[@TheErudite21]

David Pearce Well said! Great way of looking at it. This becomes especially apparent when one really grasps the breadth of this 'Age of Information' where Big Data goes further than any one of us could truly imagine. Such an overabundance of information will indeed create gradients of consciousnesses and imagination as biotech directly connects and catalyzes this vast network of knowledge... I personally don't trust humanity to make use of it so fluidly as you suggested though... I suppose it all depends on how we as individuals and influences shape the age to come...

[@straightupkid]

insightful and eye opening

[@esguerraaaliyahd.342]

love your creativity andddddddddddd the lessons :)

[@utkua]

if everyone was always happy, there would not be a civilization since there would not be need to cooperate, there would not be need for companionship, there would ultimately no humanity at all

[@G3Number]

Life is about balance so simple to describe yet so difficult to be

[@danielapazccc2684]

Well, I actually needed this

[@OlivierRovelli]

That made me feel a bit better i don't know why. Interesting anyway !

[@GOODBOY-vt1cf]

thank you so much

[@emiliadragulin5826]

I would like to see more about this subject :)

[@anthonygerace8926]

Very profound presentation, in my opinion. A good point was made about how talking about sadness helps to alleviate it. However, in our current society (and probably in many societies throughout history) many people feel so isolated that they believe that there is nobody for them to talk to. Some of those people -- if they have the financial means to do so -- then, in effect, hire "listeners" -- psychiatrists, psychologists and therapists. Another way that our society professionalizes and monetizes almost everything.

[@StanleyKingChan]

this video creeped me out a little. when the depression monster came out the tone of the video changed to be creepier...

[@shikamarunara8920]

i have found that this video gave me both healing like and soothing states of mind . (that is an understatement as i am not that great at expressing myself, i try al the same) thanks alot

[@shikamarunara8920]

all the same* lol

[@nv2142]

Melancholy is that small rustle in my chest which is always followed by a sigh.

[@addiemeier5168]

A life without suffering isn’t living. I want to cry and scream and feel. I want all my emotions

[@sharonlyounkin]

Great video

[@maiky2388]

Very good !

[@hanabern3897]

A year ago i do productive things when im sad or depressed( im a pessimist) but i talk it out to my bestfriend. He said i need to get out of that phase, it doesnt bring joy and contentment even you did alot.

[@robbieaulia6462]

Without ever feeling sad you will never feel what is happiness, basicly the universe can only exist if the light and the dark both exist, take an example from planet that orbit dwarve stars the does not rotate in place one place will always be noon and one place will always be night without night you'll ve burning alive, and without noon you'll freeze to death, I love the fact that the universe always tries to teach us what they truly are

[@crowofcainhurst]

I wish I'm the type of person who experience that burst of creativity during depression/sadness. Unfortunately all I feel when sad is emptiness, disinterest to do things I usually enjoy.Completely incapacitated and only seek solace on drugs and alcohol.

[@blakeaross]

I'm very interested in studying what was referred to when it was said that cultures that say 'heartbreak' vs. 'heart bruise' seem to have different subjective experiences. Is this research you could direct me to? I can't seem to Google it.

[@TheCourtneyjune]

Hi Blake, you might check out The Illness Narratives by Arthur Kleinman, who is a medical anthropologist teaching at Harvard.

[@imnecla]

I feel so good :) thank u

[@phillipmiller4642]

Great Video

[@8Ragas]

This is beautiful :)

[@garythomas2653]

People have always called me a miserable so and so, but I wanted to explain to them it is melancholy

[@sakuranovaryan9261]

I'm tired of always being the one who listens to people. And ends up with nobody to talk to when I'm in pain. Atleast when I talk to my therapist I won't feel so bad about it cause I'll be paying her. But she won't be a friend or family. I can't complain. I dont wanna cause I dont wanna overwhelm anybody with my burdens.

[@doxologist]

Robert Burton's quote was from the bible - Ecclesiastes 1:18 where Solomon said "For he who increases wisdom, increases sorrow"

[@zigalkodonverven3862]

So that's where "Hope is the thing with feathers" comes from! I always thought it was the name of a book about the extinction of 6 bird species.

[@TheNin-Jedi]

If we rid ourselves of melancholy then we lose the best parts of our souls. Melancholy in my personal experience has helped me more than destroyed me. If you never experienced it then you don't even know what music really is.

[@randomvicky939]

I guess we’re not only living in a fractal dimension but also in a elegant simbioses . Everything that happens outside is a reflexion of inside . It also explains the law of polarity ( from the book the Kybalion ) , which brings me the idea that everything you want comes with something you don’t want . So melancholy is just a state in which we should take advantage for learning like everything else in the world.