Solving the climate crisis is the greatest and most complex challenge that homo sapiens have ever faced. The main solution, however, is so simple that even a small child can understand it. We have to stop our emissions of greenhouse gases.

I have Asperger's, I'm on the autism spectrum, so I don't really care about social codes. It makes you think differently.

We can't just choose to tell some facts and not others because we don't want to upset people. We have to tell it like it is.

Many people seem to have this double moral. They say one thing and then do another thing. They say that the climate crisis is very important and yet they do nothing about it.

We have to understand what the older generation has dealt to us, what mess they have created that we have to clean up and live with.

I like school and I like learning.

For way too long the politicians and people in power have got away with not doing anything at all to fight the climate crisis and ecological crisis.

I have been on the road and visited numerous places and met people from all over the globe. I can say that it looks nearly the same everywhere I have been: The climate crisis is ignored by people in charge, despite the science being crystal clear.

I don't use any animal products, both because of ethical and environmental and climate reasons.

I want the politicians to prioritise the climate question, focus on the climate and treat it like a crisis.

Giving up cannot be an option.

I have always been that girl in the back who doesn't say anything.

Some people can just let things go, but I can't, especially if there's something that worries me or makes me sad.

Sometimes it's Tune-berg, sometimes Thunn-berg. I mean, I think it's funny that everyone pronounces it differently. So, that is just - I don't mind anyone pronouncing it wrong. There's no wrong way to pronounce it. Everyone pronounces it in their own way.

When I'm really interested in something, I get superfocused on that. And I can spend hours upon hours not getting tired of reading about it and still be interested to learn more about it.

I'm on the autism spectrum. I don't usually follow social coding and so therefore I go my own way.

Many people, especially in the U.S., see countries like Sweden or Norway or Finland as role models - we have such a clean energy sector, and so on. That may be true, but we are not role models.

I know so many people who feel hopeless, and they ask me, 'What should I do?' And I say: 'Act. Do something.' Because that is the best medicine against sadness and depression.

I mean, people aren't continuing like this and not doing anything because they are evil, or because they don't want to. We aren't destroying the biosphere because we are selfish. We are doing it simply because we are unaware.

I see the world in black and white, and I don't like compromising.

Learning about climate change triggered my depression in the first place. But it was also what got me out of my depression, because there were things I could do to improve the situation. I don't have time to be depressed anymore.

I write all of my own speeches.

I have promised myself that I'm going to do everything I can for as long as I can.

I think in many ways that we autistic are the normal ones and the rest of the people are pretty strange. They keep saying that climate change is an existential threat and the most important issue of all. And yet they just carry on like before.

If there really was a crisis, and if this crisis was caused by our emissions, you would at least see some signs. Not just flooded cities, tens of thousands of dead people, and whole nations leveled to piles of torn down buildings. You would see some restrictions. But no. And no one talks about it.

Some people say that I should study to become a climate scientist so that I can 'solve the climate crisis.' But the climate crisis has already been solved. We already have all the facts and solutions. All we have to do is to wake up and change.

It is hard sometimes to always be at the centre of attention, but when you talk about me you also have to talk about the climate.

I do not see myself as a celebrity or an icon or things like that... I have not really done anything.

Not having hope is not an excuse for not doing something.

Some people say that the climate crisis is something that we will have created, but that is not true, because if everyone is guilty then no one is to blame. And someone is to blame.

My message is that if we do not care about the climate crisis and if we do not act now then almost no other question is going to matter in the future.

Many people say that this is not an easy issue, we cannot just say that this is how it is, it's not black and white. But I say that this is black and white. Either we stop the emissions or we don't. There are no gray areas when it comes to survival.

People are underestimating the force of angry kids.

It is our future on the line, and we must at least have a say in it.

My message to the Americans is the same as to everyone - that is to unite behind the science and to act on the science.

Even if the politics needed doesn't exist today, we still need to use our voices to make sure that the people in power are focused on the right things. Because this is a democracy, and in a democracy, people are the ones who run the country.

Nothing is being done to stop the climate and ecological emergency from happening and to secure the future wellbeing for future generations.

I really miss having a routine because now I've been on the road constantly for several months. I like routines, so it would be nice to get those routines back.

My message to all the activists is to just keep going, and I know it really may seem impossible and hopeless sometimes - it always does - so you just have to keep going because if you try hard enough and long enough you will make a difference.

It's empowering to know I am doing something, I am taking a stand, I am disrupting.

We are not going to be satisfied by politicians saying 'we support you' and then walking away. We won't be satisfied until they meet our demands and act. That's why simply taking a selfie or posting support on Twitter isn't enough. That's why we have to keep striking.

I feel strange when I get applauded by people in power... because it's obvious that it's them I'm criticizing, but they can't show that in front of the cameras. It's quite funny sometimes.

There's always going to be people who don't understand or accept the united science, and I will just ignore them, as I'm only acting and communicating on the science.

Sweden is not a green paradise, it has one of the biggest carbon footprints.

The best thing about my protest has been to see how more and more people have been coming and getting involved.

I believe that one person can make a difference.

Avoiding climate breakdown will require cathedral thinking. We must lay the foundation while we may not know exactly how to build the ceiling.

When I have been travelling around to speak in different countries, I am always offered help to write about the specific climate policies in specific countries. But that is not really necessary. Because the basic problem is the same everywhere.

Some say we should not engage in activism. Instead we should leave everything to our politicians and just vote for a change instead. But what do we do when there is no political will? What do we do when the politics needed are nowhere in sight?

We are at a time in history where everyone with any insight of the climate crisis that threatens our civilisation - and the entire biosphere - must speak out in clear language, no matter how uncomfortable and unprofitable that may be.