Two years ago Rathbone was panned by psychologists and cyber bullying experts over the controversial website that promised to be "like Yelp or TripAdvisor for humans".

The premise, then, was users could create a public profile for themselves, and review others, and those reviewed could then respond to both praise and criticism.

But psychologists labelled the idea dangerous and disturbing and aired concerns about privacy issues. Rathbone, along with co-developers, his brother Dayne Rathbone and software engineer Monish Parajuli, shelved the idea.

"We were probably a bit naive about the concept, which was, in all honesty, an abstract concept, when we did the first media in 2015," Rathbone admits.

"We always knew that the content in Karma was going to be overwhelmingly positive, we just had to create the right space."

And so know Karma has been relaunched. And it's morphed into that space Rathbone knew it could be, a place for people to express gratitude to others in their life, through letters and stories. Close to 3000 letters have been posted, to family, to friends, to work colleagues, mentors and team-mates. People are writing for birthdays and weddings, on sadder occasions when someone is ill, or has died, people are writing for no reason at all, other than to say thanks.

"It's so rare to sit down and actually meditate on the positive impact someone has made on your life and to express that is a powerful thing," Rathbone said.

"I think the motivations are twofold, one you want to give a unique, powerful gift but more and more users are telling us that the benefits to them, as the author, are really powerful as well. The whole science around gratitude is becoming more mainstream and this taps into that."

Rathbone said the central message of Karma is about meaningful human connection. While the first letters read like resumes, "Dayne is loyal, Dayne is reliable", the real power of the site began to emerge once people started telling stories.

"The best letters are stories," reiterates Dayne Rathbone.

"When we started off people were expressing gratitude by writing about their good qualities but the thing we drilled down into was the power of human stories.

"When you tell a story about someone the authenticity of the story and that person exudes out of the letter.

"You're remembering something you were grateful for and it's way more meaningful and creates a real connection between people."

So far the Karma team has not had to deal with any trolls. There are no anonymous posts. Recipients of the letters are alerted when someone posts about them and are always given the first right of reply. It is free to post a letter, free to join the site.

There are loose plans around making money. They recently produced a book full of letters written to the one person and there are plans for Live Letters events where people could read their letters to each other.

"The biggest thing we've learned is that there is a tremendous amount of good people in the world," Clyde Rathbone said.

"You don't always get that message from traditional news and particularly social media."

As part of the Canberra Writer's Festival Rathbone will be delivering sessions entitled "Rethinking Social Media", that look at the research that suggests the more we use social media the worse we feel. It will also address the Karma journey.

"The whole idea of karma for us, it's the perfect name," Rathbone said.

"While there might have been problems at the start, our belief in this, our belief it would be overwhelmingly positive has turned out to be accurate."

Clyde Rathbone: Rethinking Social Media, Saturday, August 26, 4pm, and Sunday, August 27, 4pm, National Library of Australia. The Canberra Writer's Festival runs from August 25-27.