Define the "Carpe diem" philosophy. What are some pros and cons to living this way?

Carpe Diem is Latin for "seize the day." Mr. Keating encourages his students to "suck the marrow" out of life. They should take chances and risks, within reason, to discover the potential of life. This is the way to realize greatness in oneself. It also has risks of failure when "seize the day" does not work out the way you wanted it to. I suppose the pain of loss is part of "seizing the day."