Since the 1950s, when he began teaching German history, Professor Mack Walker has been interested in an intellectual phenomenon of the late 17th and early 18th century--a divergence of secular and religious language.

"It has to do with a breaking point in European culture generally, I suppose," Walker said recently, "when worldly language and spiritual language separate out around 1700 as ways to understand and describe experience, and they don't know just what's happening."

Mack Walker, who has been teaching at Hopkins since 1974 and will retire at the end of June, says he "got involved with the Guggenheim ... to keep active intellectually."

About four years ago, Walker began to curtail his teaching at Hopkins in preparation for retirement. He also began looking more closely at this phenomenon. Now, with full retirement approaching at the end of June, Walker has won a Guggenheim Fellowship to pursue this research question.

"It will enable me to continue the research that I've been doing over the past two or three years with resources from the university, which end this year," he said. "This in effect replaces those for a period of a few years."

To get a handle on the very large intellectual question, Walker chose to examine it in terms of two prominent German professors and intellectuals of that time--one a professor of law, and the other a religious leader and organizer.

The two men--Christian Thomasius, the jurist, and August Francke, the pietist preacher--were colleagues for decades and, at intervals, friends, rivals and enemies.

Set at the University of Halle between the 1680s and the 1720s, the oftentimes rancorous dialogue between these two intellectual heavyweights personifies the larger question for Walker.

"They're using very similar language at the start," he said. "For example, Thomasius and Francke use the same words for a breakthrough intellectually, the same words for a religious breakthrough. They use language of illumination or enlightenment for both--that sort of thing. Because of the ambiguity of the situation, they don't quite follow where either one of them is going, you know."

He plans on writing a sort of "dual biography involving the encounters of these people when they're friends, when they're enemies, what the issues are, how they cope with one another and so on. This gives me a way to do it, which is one of the things I had wondered about for a long time."

On a personal level, the story of these two men seems quite captivating, even without the larger intellectual question. Walker said, for instance, the two were young junior faculty members at Leipzig, got kicked out together for "being too fresh" with senior faculty, went to the University of Halle together and were, at times, very close friends. Thomasius, for example, used to go to confession before Francke.

His plan for this research is to examine the question through a series of episodes between the two academic leaders.

"I think it's complicated enough to keep me interested, to try to do this right," said Walker, who will turn 70 in June. "Indeed, that's one of the principal reasons I got involved with the Guggenheim, because I wanted to, with retirement, keep active intellectually.

"And now I kind of have to," he added, with a smile.

His Guggenheim award, Walker said, will enable him to continue the research for several more years, including traveling to Germany to examine source material in Berlin and the University of Halle and Francke archives.

Walker, who has been teaching at Hopkins since 1974, has published books on German history and has won other fellowships, including a Guggenheim in 1972, which he turned down because he had also won a fellowship from the National Endowment for the Humanities that same year.

On Tuesday, May 11, Walker will give a valedictory lecture (see Calendar for details).