In Ian McEwan's book "Saturday," the protagonist reflects on the overwhelming nature of significant global issues like politics, climate change, and poverty, which can lead to a sense of hopelessness. These large-scale problems can overshadow personal experiences and achievements, making the future seem uncertain and dismal.

In contrast, the character finds joy and optimism in focusing on the smaller, immediate aspects of life—relationships, enjoyable activities, and personal moments. This shift in perspective leads to a personal motto of "think small," highlighting the importance of cherishing everyday joys and connections to counterbalance the weighty problems of the world.