In his rise to online fame and fortune, Masayoshi Son has stirred up more than his fair share of controversy.

But the head of Softbank, Japan's leading internet investment group, waves away current problems - such as the slide in high-tech share prices or accusations that its planned purchase of the failed Nippon Credit Bank raises serious conflicts of interest.

Instead, he prefers to peer beyond the horizon, seeing a bright future for society, in Japan and elsewhere, if the opportunities of the digital revolution are grasped.

"I feel sad when people don't understand our real vision and passion for this whole revolution," he says. "But I am confident that our philosophy and our passion is genuine and that we will help society to reshape."

This vision has proved both a blessing and a curse. "Son is not very good at analysis. He is more of a big picture guy," says one person close to the company. However, amidst the swirl of deal-making, stock market activity and ambitious global expansion plans at Softbank, investors and analysts are keener to concentrate on what Mr Son is doing now rather than on how he sees the coming decades.

Softbank has grown so fast and in so many directions that even its own executives have trouble asssessing its progress and navigating its complex financial structure. While its shares were soaring - and Mr Son was being spoken of in the same breath as Microsoft's Bill Gates - such reservations tended to be pushed aside.

But having climbed by more than 1,000 per cent in 1999 and reached nearly Y200,000 earlier this year, Softbank's shares succumbed to the US-led rout in internet and information technology stocks. They recently slumped to below Y8,000, severely affecting the wealth, on paper at least, of Mr Son, who owns 38 per cent of Softbank. At the peak, his holding was worth $70bn.

As well as cutting the value of Softbank itself, the market slide also weakened the prospects for new company flotations - including many of those nestling under the Softbank umbrella. The group recently cancelled its plans to list five group companies, giving the strongest signal yet that the company which seemed impervious to market troubles was rethingking its strategy.

But Mr Son - at least in front of reporters - remains unruffled. "The market goes up and down, you know. It's like the weather. Do you decide to become a golfer because today is a sunny day and then decide not to become a golfer because the next day is rainy?"

No, says the casually-dressed, soft-spoken Mr Son, himself a keen golfer, with a photograph on his office wall of him and Bill Gates riding in a golf cart. "You shouldn't decide the long-term vision or strategy based on just a changing climate. I'm more focussed on the long view, the vision and strategy."

Thus he expects the market to settle down, the conditions for initial public offerings (IPOs) to improve, and young entrepreneurs to be encouraged as they build up their businesses with a view to eventual listings.

"We have increased the number of our family companies from one internet company five years ago to 140 last year. Today, we have over 400 internet companies. By the end of this year, we will probably have 500."

These include some of the biggest names on the internet stage. Softbank owns 23.5 per cent of Yahoo!, which it brought to Japan; its stake in Yahoo! Japan is 51 per cent. Softbank also has sizeable minority holdings in E*Trade, E-Loan and other online companies.

"It's important to bring in organisations which can accelerate the success of the whole group," he adds. "Each company is bringing synergies and more success - bringing a revolution to the way people live in society."

People close to the chief executive, however, suggest a different story: the recent market turmoil has unnerved the board of Softbank, which is Japan's only board composed mainly of outside directors. There is talk, insiders say, of fewer IPOs of subsidiaries; some even whisper about a cash flow problem.

"We are having a rethink," says one executive. "We need to become more market-focussed and realistic."

In an industry dominated by US entrepreneurs, the rise of Softbank to its present size and shape - with ambitions to extend its operations in Asia, Europe and Latin America - is a phenomenon in the conservative Japanese business scene. But Mr Son, 42, is an outsider in Japan's tightly knit consensus-minded society. An ethnic Korean, born in southern Japan, he was educated in the US.

He studied economics at Berkeley, California, and founded Softbank nearly 20 years ago after his initial business ventures. While his involvement in the magazine business, through Ziff-Davis, was not a success, his decision to invest in Yahoo! in 1995 laid the basis for Softbank's rapid growth.

Today, Softbank has built on that investment to become one of the most aggressive internet companies in Japan. Mr Son is personally keen to push the benefits of the internet beyond his corporate empire. "Japan is behind the US in many many aspects of the internet," he says. "So we have to accelerate in all of these aspects."

That, he says, is why he is involved in Nasdaq Japan (in partnership with the US Nasdaq exchange) and the nationalised Nippon Credit Bank, which he wants to develop into an online operation, especially in the business-to-business area. Softbank and a consortium of other companies agreed in June to buy the bank from the government.

The NCB deal was delayed by the government in the face of criticism over the terms of the contract and treatment of bad loans, but is now going ahead.

There is understood to be great division about the purchase within Softbank. And the proposed acquisition has also raised serious questions about Softbank's credibility with investors, as analysts have been concerned about the possible moral hazard of owning a bank that funds internet companies.

Yet however the NCB deal works out, Mr Son has much more in the pipeline. Like most Japanese internet executives, he wants more business deregulation and more spending on telecommunications infrastructure to bring faster access speeds and lower tariffs for internet usage.

He also wants the Japanese government to be more assertive against the dangers of computer viruses and hackers. "They have to attack those issues in a more pro-active manner."

As for the vexed issue of interconnection charges, he supports efforts to persuade Nippon Telegraph and Telephone to bring these down. Under US pressure, NTT, which owns 90 per cent of Japan's local telecoms net work, recently agreed to lower access charges to rival operators. "The monopoly situation is only good for NTT and bad for everybody else."

Although Softbank companies cover some 85 per cent of Japan's internet users, Mr Son says the real potential of this reach can only be realised if online industries prosper in a more favourable business environment.

"If young entrepreneurs have a much better environment in which to bring more internet companies into being, that will increase internet users, that will improve access speeds, that will bring more content, more communities, and so on."

Mr Son says he is speaking as much for business and society as a whole as for Softbank. That is why he is keen to promote more B2B activity by developing NCB into an online bank. Mr Son is determined to push his vision across Japanese business and society. Ten or 20 years from now, he believes, "they will understand what we were intending to do".

But meanwhile, he believes, a combative spirit is needed - both at Softbank and the companies in which it has invested. "If you play Nintendo," he concludes defiantly, "there are always monsters at each stage. You have to fight to become a real strong hero."

Mr Son has no doubts that he will ultimately emerge victorious. His critics, though, would rather wait and see.