What is the theme in McTeague: A Story of San Francisco by Frank Norris?

Nature is another theme to consider. The idea that one is not responsible for, or capable of changing, his or her own makeup is a predominant theme throughout this book. Trina justifies her miserly ways by saying she "can't help it." McTeague alludes to the fact that his violent and drinking ways are due in part to his father's passing those traits down to him.