The quote emphasizes the importance of mental engagement and activity for maintaining intelligence and cognitive strength. It suggests that passivity, particularly through distractions like television, can hinder our intellectual growth. Just as muscles require exercise to stay fit, our minds need stimulating challenges to thrive.

The author, Mark Helprin, illustrates a profound connection between physical and mental fitness, urging readers to take control of their thoughts and experiences. By actively participating in life and resisting mindless consumption, individuals can ensure their intellect remains sharp and vibrant.