Is anyone truly unselfish?

While I was in college, a professor asked our class if we thought it is possible to perform unselfish acts. Of course, most of the class said it is. People dedicate holidays to work in free kitchens for the homeless, we give people money on the streets, we open doors for people, we donate old coats in the winter, we let people get in front of us in line at the grocery store if they have a few items and we have many, we give gifts to needy families at Christmas time. The list goes on and on.

This professor said we get things in return. He said, chances are, we feel good about doing these things for people. I mentioned to him that most people probably don't do them for the warm fuzzies we get out of it. He said it said it doesn't matter. He says they aren't selfless acts because we get something in return: we feel good about ourselves.

I obviously think it is possible. What do you think?