One day Maureen Mulligan walked into class without her usual swagger. We watched her strained face as she sat and joined the circle of desks she created to bring our CORE class closer together in room 304 of Debartolo Hall.

"They've got me loaded up on pills today to help with the pain. I feel like I'm in space," she said with an annoyed grin.

That's all it ever was for Professor Mulligan: an annoyance that her recurring bouts with breast cancer got in the way of her rigorous routine of teaching, learning, and the enjoyment of being a mother to her two sons, and loving wife for her husband.

We all smiled along with her; after all she had already talked with us months before, on the first day of class, about how her bouts with cancer might cause her to miss a few days.

She apologized to us, saying "I've beaten it before, and I'll beat it again."

She had us fooled, because we didn't have the slightest idea what was going on.

The emotional first-day speech faded into our memories, and class went on without illness entering our minds.

One day she brought a friend of hers who was legally blind into class so we could learn to see the world in a different way. It was something special in class that day, and it changed the way I looked around me. She often talked of her childhood, and of her kids and husband. However, she rarely mentioned the condition that was destroying her future.

Weeks later, during a discussion of nature, she opted to lead us on a march all the way around Saint Mary's lake on one of the last warm and sunny days last fall. She pointed out every different kind of flower on the banks of the lake by name. We saw the leaves beginning to paint the entire forest. We saw swans dipping their heads underwater to escape the sun.

"Do we have to go all the way around the lake?," someone complained. "Class is almost over and my shoes are muddy."

Professor Mulligan gave him a look of shame, as he well deserved. "C'mon now, we're halfway back," she said with the tone of a coach pushing an athlete to the next level. "Besides, look at this beautiful day. There aren't many of these left." We all missed the irony.

Soon after, the weather at our University changed. One day when the Golden Dome was first laced with a delicate snow, we entered room 304 and our professor wasn't there. Our substitute read from the detailed instructions left by Professor Mulligan: more medical tests were being done, she was sorry, she would be back as soon as possible, we must keep up with the readings and discussions.

When we left for break, we expected to return in January with another semester of Professor Mulligan's sarcastic humor. We expected to receive the kind of insight only gained from a person who has never taken shortcuts, but instead has opted to enjoy all the foliage of life.

Maureen Mulligan died on Saturday, at her home in Dowagiac, Michigan. She missed only three days of class the entire semester, and was successful in keeping our focus off of her, and on our class material.

Next time it won't be me who complains. I will take advantage of my opportunity to always go all the way around the lake, and will appreciate every heartbeat while the warm weather lasts.

• In Appreciation