[CAUTION: This interview contains a major spoiler. If you haven't read the end of the manga Nausicaa, you might not want to read it.]

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The Fukai (Sea of Corruption) in Nausicaa of the Valley of Wind was a system which humans made one thousand years ago to clean up the environment. But even those who created it could not predict how the Fukai would change. No matter how many excellent ecologists work together, you can't (predict it).

For example, we can plant a camphor tree next to this office (Studio Ghibli). But we don't know what will happen to this tree. We can't predict what this tree will bring to humans: if it gives someone an opportunity to fall in love, or if it falls down and brings this building down. It's arrogant to think that we can predict. Humans can make a start, or set things up, but we can not determine what will stay there, or whether a god will stay there or not.[1] I think this is a more appropriate way to see this world.

The things intended and the things that come about are different. So, the Fukai started as an artificially engineered ecosystem, but it changes into something different over time in this world. It suits my feelings better to think that even an artificially created forest can properly function as a forest, and becomes an ecosystem complicated beyond our imagination, than to think that it's no use to care about it, since it's not a natural forest.

The idea that Nature is gentle, and it creates the Fukai to recover the environment humans contaminated, or does something (for humans)-- that's not true. Clinging to such a naive view of the Earth is problematic. I came to think this way while I was writing Nausicaa.

I had a feeling that it would end this way, from the beginning. Some said that that's not good, since (such an ending) would betray the readers. But, it (the Fukai as a natural ecosystem) isn't right. There can't be an ecosystem with a purpose. I didn't want to go there, but I had to. And although Nausicaa knows the truth about the Fukai, it's almost impossible to explain it to people by words. If (readers can see) what she has been doing, and can feel what she is going to do from now on, that's enough. We can't talk about hope so easily.

Then, what is hope? Going through hardships with those whom you care about, maybe that's hope, too. We have no choice but to think that to live means such a thing. I ended up thinking that way.

I don't know what would happen if I planted grass and cleaned up the river. Will it lead to future? No, it wouldn't. But, if I don't do anything, nothing will happen. And at least some troubles happen to my daily life (by doing something). (I decided to) enjoy them.

But the minute we say that we don't know what would happen, that we have no choice but to let it happen, we get another problem. I can see what would happen. The phrase in the song, "Saigo no News" (The Last News) by Yousui Inoue; "Humans overflow the earth, and they fall in the end of the sea"-- that's it. Whether we think about it or not, it's laid in the consciousness of us all.

Right now, if we divide all the land area on the Earth, including deserts and the polar region, by the population, we have 170 meter square per capita. Fifty years from now, when we have 10 billion population, it will be 120 meter square. When it becomes 50 billion, there wouldn't be any other creatures than humans. Asimov, the science fiction writer, calculated that 50 billion is the limit imposed by the organic materials made by photosynthesis on the Earth.

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We have no choice but to think that humans can become 10 billion but also could become 200 million in the future, and that's human. As there were numerous examples in history, there will be countless tragedies in future. Then, what should we do to live? We have no choice but to have a lot of children. We have no choice but to think that to live means to live being troubled by your children, to live suffering from disease. So, these days, when I'm invited to a wedding, I just say, "have a lot of children." It's no use thinking about the future. I don't mean no use, but, humans are such beings. So if you ask me which is better, it's better to have children, and to be troubled by them.

If we say nothing works, of course nothing works. But you are going to die someday anyway, so if you say it's no good, everything is no good. But, humans have stopped going extinct. That's for sure.

It's been said that dinosaurs went extinct as a result of the evolution, but the story has changed recently. It wasn't Nemesis who gave them a punishment they deserved, but it was a huge meteorite which crashed on the Earth, and brought a climate like nuclear winter, that killed the dinosaurs off. Or, (another theory says) it wasn't a meteorite, but the Earth which went through an era of big crustal movement. Volcanoes erupted and 70 precent of species went extinct, renewing (the ecosystem). The Earth is not gentle. If it were not for that, the dinosaurs would have continued to thrive. They perished not because of themselves, but because of the Earth.

At the end of the twentieth century, it became the general theory. It means that humans have decided to live, even though we keep expanding without limits, and producing pollution.