"Let's not look to the people in power to change things, because people in power are among the emptiest in the world... they're never going to change unless we make them."
Severn Suzuki - daughter of the renowned conservationist David - went to the Rio Earth Summit 20 years ago as a 13-year-old to ask her elders to sort themselves out.
That 1992 speech was caught in full on video and it's now one of the most frequently viewed YouTube offerings on environment and sustainability.
What I think caught people's attention was the mood. You might imagine that a 13-year-old girl would talk about emotive things like dolphins and rainbows, and talk in pink generics such as "making the world a better place".
Not a bit of it. Ms Suzuki lays into the delegates: "I've come to tell adults you must change your ways... I'm fighting for my future".
She points out that as yet there is no technical remedy that can clean up mercury pollution or PCBs.
"If you don't know how to fix it - please, stop breaking it," she says.
This year, back via webcam holding one of her own children, Ms Suzuki was no less impassioned, though the message carried a strong flavour of frustration and an occasional hint of despair.
