Two thousand years ago, the Roman poet Horace advised his readers to “think of each day as if it were to be your last,” and to seize the day (Carpe Diem!) because you cannot trust what tomorrow will bring. His purpose was not to instill pessimism and fear but to urge us to find joy in each day and to be grateful for every new day, treating it as an unexpected gift. How much happier could you be, and how much more would you accomplish, if you could truly adopt this mindset?