Twenty years ago, when Angel and I were just undergrads in college, our psychology professor taught us a lesson we’ve never forgotten. On the last day of class before graduation, she walked up on stage to teach one final lesson, which she called “a vital lesson on the power of perspective and mindset.” As she raised a glass of water over her head, everyone expected her to mention the typical “glass half empty or glass half full” metaphor. Instead, with a smile on her face, our professor asked, “How heavy is this glass of water I’m holding?”

Students shouted out answers ranging from a couple of ounces to a couple of pounds.

After a few moments of fielding answers and nodding her head, she replied, “From my perspective, the absolute weight of this glass is irrelevant. It all depends on how long I hold it. If I hold it for a minute or two, it’s fairly light. If I hold it for an hour straight, its weight might make my arm ache. If I hold it for a day straight, my arm will likely cramp up and feel completely numb and paralyzed, forcing me to drop the glass to the floor. In each case, the absolute weight of the glass doesn’t change, but the longer I hold it, the heavier it feels to me.”

As most of us students nodded our heads in agreement, she continued. “Your worries, frustrations, disappointments, and stressful thoughts are very much like this glass of water. Think about them for a little while and nothing drastic happens. Think about them a bit longer and you begin to feel noticeable pain. Think about them all day long, and you will feel completely numb and paralyzed, incapable of doing anything else until you drop them.”