Norbert Walter was a man full of thoughts, principles and charm. He was keen to think, provoke, entice and educate till his last breath.

He did all that — but with at least a quarter century of energy, wit and ideas left in the tank. Sadly, with his premature death on August 31, we will not benefit from all the intellectual energy and courage this man possessed.

I still remember vividly one of our first interactions. In the early days of the Clinton Administration, way back in the spring of 1992, we went to visit Bob Rubin in the White House. The former Goldman Sachs CEO's tenure as Treasury Secretary was still in the future. At the time, he was serving as the first director of the National Economic Council.

Rubin received us in his new office, a relatively small, wood-paneled room. It seemed unremarkable in that it felt like the undistinguished captain's quarters on a small ocean-going ship. His new office surely had none of the trappings of a former captain of Wall Street (though it had a trophy location on the floor above the Oval Office).

"So Norbert, tell me what's happening in the world," Rubin said with well-practiced, but efficient understatement. "Now that I am no longer CEO of Goldman Sachs, I feel out of the loop. All I can rely on is my yellow pad and listening to people like you."

And so he listened attentively to the 47-year old German economist who, uncharacteristically for his nation, never lacked for an opinion on anything. Stranger still for a German, Norbert Walter was constructively gutsy — and generally disinclined to play it safe.

In a world flooded with vapid statements but full of real-life problems, Norbert Walter usually went all in. Most recently, I saw his unflinching intellectual courage on display at the INET conference in Berlin in May of this year.

Norbert had done what few of his colleagues would have dared to do, going into the lions' den of a pool of largely Keynesian economists who are decidedly not in favor of fiscal consolidation at the present time.

It was an article of faith that Norbert cared more about seeking common ground with those ardently opposed, rather than stew comfortably in a pot of like-minded people.

So he waded right in, telling them why, even in these circumstances, it would important to have a firm plan in place to tighten public expenditures, so that the aftermath of the crisis would not turn out to be worse than the crisis itself.

His viewpoint was clearly not appreciated by most of his audience that day. But it was an article of faith — and a telltale sign of Norbert's true humanism — that he cared more about seeking common ground with those ardently opposed, rather than stew comfortably, but unconstructively, in a pot of like-minded people.

Norbert's contrarianness even extended to his dress code. The world of investment bankers is full of pinstripe suits and cashmere coats, but not C-levels wearing parkas for a winter coat.

So it was always a particular pleasure during my visits to Frankfurt to see Norbert enter the elevators with his all-dressed-up colleagues in the Deutsche Bank towers. They weren't sure whether to show bemusement or disdain, and he wasn't sure whether he should be bemused when he looked back at them.

When he came to dinner at my home in Washington, green asparagus had to be on the menu in some form or other. In those days, green asparagus was an unknown in Europe.

Green was also what was on the plate of Bill Bradley, the U.S. Senator, who preferred to eat his lunch salads even without any dressing. (Such is a former NBA basketball star's determined fight against taking on calories.) He and Norbert always had feisty, but very constructive, exchanges about the post-communist route of Russia and on debt forgiveness for poor nations.

Friendly quibbles also with Bob Zoellick, then at the State Department — then, as now, somewhat boyish — and still some career steps away from becoming World Bank president.

Less friendly were the intense sparring sessions with Larry Summers, who had little appreciation for many of the key features of the German economy.

Less friendly were Norbert's sparring sessions with Larry Summers, who had little appreciation for many of the key features of the German economy.

To Summers, Germany spelled unemployment, social policy laxities, structural weakness, overregulation and no growth. And in the margins of those early meetings, if memory serves, sat Tim Geithner, Summers' special assistant, as note taker.

Norbert appeared often on TV news programs in the United States. Back in 1990s, with German reunification, the self-liberation of Eastern Europe, and the launch of the euro in the news, Norbert's views were much in demand. He also published frequent opinion pieces in the New York Times.

In a magnificent display of how those pieces written for a U.S. audience echoed back into Europe, the German mass tabloid Bild — the very conservative tabloid then published in Hamburg — picked up one of Norbert's New York Times op-eds.

The paper made waves by suggesting on its front page that the Deutsche Bank chief economist wanted to send all those then-large numbers of unemployed Germans to the United States, where there was a worker shortage at the time.

Norbert always knew to create a sizzle where one was needed, but not even he would have shortened the arc of his argument quite to that very point.

The news sure made waves throughout Germany. Which is exactly how he wanted it to be, either by accident or by design. To him, Germany needed shaking up. Constantly.