One of the central preoccupations of the arts and humanities is the observation of human beings. Painters and sculptors create images of the human form ; writers tell stories or compose poems about human experience; musical artists give melodic contours to the human spirit; historians and philosophers ponder the essential qualities of human civilization and nature. And in our own lives, in our own ways, we spend a great deal of our energy and attention on our fellow creatures, being in families and other kinds of relationship, observing people with curiosity and interest in the course of the day, thinking about and forming our own character — deciding what kind of person we wish to be — as we grow. Which is the topic sentence?