Groucho Marx is usually thought about for his biting humor. This month's quote is a little more on the thoughtful side. It even sounds like something a person might hear from a mental health provider:
Each morning when I open my eyes, I say to myself: "I, not events, have the power to make me happy or unhappy today. I can choose which it shall be. Yesterday is dead; tomorrow hasn't arrived yet. I have just one day, today, and I'm going to be happy in it." (Attributed to Groucho in 1972 by Rufus W. Gosnell, an Aiken, SC, newspaperman.)