He cut the brain stem from the rest of the brain and looked at the substantia nigra, dark lines that run through the midbrain. In Parkinson's disease, these lines lighten. The lines in Moore's brain had lost some pigment, but less than usual for Parkinson's.

Using a long knife, Forman sliced the gelatin-like brain in half. The center would use one hemisphere for the autopsy. The other would be frozen and used only for research.

Again, Forman, a wiry, graying man whose grandmother had Alzheimer's, noticed atrophy. The ventricles - pools of cerebrospinal fluid - were much larger than normal, a sign that surrounding tissue had died.

Forman cut the hemispheres into half-inch slices. Each had brown scalloped edges - the gray matter or nerve cells - and creamy, white centers - the electrical wiring. He saw no signs of tumors or stroke.

The big-picture work over, Forman took samples from about 20 parts of the brain, including the hippocampus, the seat of memory and the place where Alzheimer's is thought to start; the amygdala, an emotional center that's also involved in smell; the brain stem, responsible for involuntary activities such as heartbeat and breathing. Especially shrunken was the visual cortex, a part of the brain usually unaffected by Alzheimer's.

What Forman saw was "consistent" with Alzheimer's, but, he said, "none of this tells me definitively what the diagnosis is going to be. Every patient doesn't read the book." He still had to study Moore's brain cells.

Forman's caution would prove justified.

Early memory loss

Bob Moore began complaining about his memory to his doctor in 1985. He wasn't even 60 yet, and the doctor discounted his fears. Most people don't have noticeable problems until their early- to mid-70s.

By 1988, Bob Criswell, pastor of the church that Moore attended, was also concerned. He pulled Moore aside to tell him he was repeating himself.

"Does it show that much?" Moore asked.

A few months later, his assistant at the presbytery, Bob Bolt, gently told Moore that he was returning phone calls more than once.

Within days, Moore, who'd had some health problems and was feeling the stress of his job, announced his retirement. He was 62.

Still curious and energetic, he began teaching philosophy at the University of Delaware's Academy of Lifelong Learning. But late in 1992, after he struggled with an ambitious class on philosophy and religion, he questioned his students. They said he'd been making mistakes.

Moore demanded an appointment with a specialist. A psychiatrist told him that he probably had Alzheimer's.

"How long do I have?" Moore asked.

"About 10 years," the psychiatrist said.

With characteristic forthrightness, Moore told each of his children. In a letter to his son Tom, now a computer consultant in New York, he wrote: "I'm in good shape psychologically. I'm not depressed... . However, I will not teach anymore. I know I could, but I also know that I have sometimes been embarrassed in classes I have taught when I have made minor slips, not just once but several times... . I am sensitive about this... .

"All people die... . I have a good chance of living many years yet, with very gradually decreased acuity."

Bob Moore did, indeed, live well for several years. He took classes and enjoyed them. He and Joanna traveled.