Ian Johnston, msnbc.com editor

LONDON — Like two emissaries of capitalism on a sensitive diplomatic mission, they came to the Occupy London protest camp bearing gifts: a bundle of free books each with a dollar bill inside, sparkling chocolate coins and a message about how some within the world of corporate finance are ready to change.

Ian Johnston / msnbc.com

"Things in the world of finance worry us too," Michael Mainelli, above, said in a letter to Occupy London protesters on Tuesday.

Professor Michael Mainelli and Ian Harris, co-founders of Z/Yen, a commercial think-tank with "intimate links" to some of London's "oldest and largest" financial institutions, might have been forgiven for feeling a little nervous.

After all, the Occupy movement was sparked at least in part by anger at the role of banks in the world's current financial troubles.

But they were not there to defend their industry – instead, they addressed a crowd of Occupiers in the shadow of St. Paul's Cathedral to express their admiration for a movement that was getting people talking about the need to reform the financial system.

"We want you to know there are a lot of people in the City (London's financial district) who are thinking about the same things [as the Occupy protesters are] in a different way," the be-suited Mainelli told the audience of around 15 people in the so-called "Tent City University" – a cluster of tents filled with books where protesters exchange their ideas.

"There is a group of people in the City, several thousands, who are interested in reform ... maybe not revolution," he added.

Story: A 'wonderful' community or just plain 'awful'? Londoners talk Occupy

Mainelli and Harris also distributed an open letter to protesters, which asserted that "things in the world of finance worry us too."

"We care deeply," they wrote in the letter, acknowledging that people are deeply uncertain about their futures and the wisdom of their governments and economies.

"We believe in asking uncomfortable, impertinent questions in search of pertinent and permanent answers," they said. "Naturally we applaud others, like yourself, who care deeply enough about these vital issues to insist firmly on debating them."

However, Mainelli made a point of saying on Tuesday, "I'm not going to be down here sleeping with you."

Financial model 'unsustainable'
Inside a large canvas tent, protesters sat on old sofas and cushions on the floor as Mainelli and Harris handed out copies of their book, "The Price of Fish: A New Approach to Wicked Economics and Better Decisions." They said it was "a gift and contribution to the worthwhile debate you have initiated."

The title of the book, which was published last week, comes from the apparent inability to come up with an accurate price for fish, Mainelli explained. Had this been done, the book argues, the Grand Banks of Newfoundland and other fishing grounds would not have been over-exploited.

The books came with dollar bills inside. Mainelli and Harris also handed out chocolate coins wrapped in golden foil.

But not everyone in the crowd seemed convinced. Suspicion of authorities is commonplace in the camp and, from the Occupiers' point of view, it is warranted: the City of London Corporation is planning to take the protesters to court Wednesday, seeking to evict them.

One listener, a bald-headed man sitting toward the back of the tent, commented that "people in positions of power" appeared to "feel so secure in their military might that they can suppress any dissent."

"How do we convince them it's not in their interest to put themselves against the whole of the planet?" he asked.

Referring to the charging of interest on loans the man added, "Your whole system (of finance) ... has got something at the root of it which is fundamentally injust."

Harris responded, saying this was "not necessarily the way finance has to be."

"There's no question in my mind that Western humanity has progressed on the back of that type of financial institution," he said, but added: "We would question whether the fundamental elements (of the system) are sustainable."

Ian Johnston / msnbc.com

Katherine Stanley, above, said she goes to London's Occupy camp to hear new arguments that might convert the movement's skeptics.

"Should there be interest at all? Does the notion of interest mean necessarily that wealth accumulates in greater and greater quantities to the few?" Harris wondered.

He said there was talk among London's financial institutions about Islamic Sharia finance, and noted that Christianity and Judaism also reject the charging of interest on money.

But could the financial system really exist without the widespread practice of charging interest on loans?

Mainelli said the idea was far from fanciful. "Extremely senior people" at large institutions "are actually really, really trying to ponder how we would rebuild [the financial system]," he told msnbc.com after the meeting.

Harris also pointed out that most state banks had reduced interest rates to nearly zero and with inflation greater than interest, those with savings were effectively losing money.

Third World War?
Protester Katherine Stanley, 49, of London but originally from Canada, saw hope in Mainelli's approach to the protesters.

"I think it's fantastic actually. He has some very good ideas about the economy ... it's a good thing he gets the ear of people who can actually make change," she told msnbc.com, expressing the hope that Mainelli or someone like him would convince those in the corridors of power.

For her part, Stanley said she goes to the Tent City University to support the movement and hear new arguments that might convert more ordinary people to the cause. 

"People who aren't involved get to hear me talk about it whether they want to or not," she said.

Ian Johnston / msnbc.com

John McCafferty, above, said he is homeless and now plays his guitar on the street.

Her 17-year-old son, she admitted, is among the skeptics of the Occupy movement.

"He listens to my stories and I bring him down occasionally," she said. "He tolerates it. He's not a fan of it, but who really wants their mother to be doing crazy stuff like this?"

Another in the audience, John McCafferty, 59, saw little chance for real change without major conflict.

McCafferty, a carpenter, said he became homeless last year after work dried up in the recession. He said he was "now reduced" to playing his guitar on the street for money.

"If we continue on our own present path, we are going direct into a Third World War," McCafferty said. "... I suspect we are heading towards a Third World War, I think that's where we are going and when the dust settles ... the hopes and aspirations of people here may be fulfilled."