I’m a scientist, so believing in things that can’t be proven is difficult for me. With COVID-19, the existential threat of climate change, terrorism, and the continuing threat of nuclear war, I’m feeling more and more like nothing makes sense and maybe life is just meaningless. This seems scientifically defensible, but it makes me feel depressed. How do I keep both my commitment to science and my mental health? Kevin: Your letter made me think back to my first research-methods class in graduate school. We were looking into empirical evidence for whether watching televised violence affects children’s behavior. One article said that by age 18 the average child has seen 100,000 murders on television. I spoke up and said, “I think it’s obvious any child would be affected in some way by watching all that violence!” The professor said, “Anderson, you’ve got your scientific fly open right now! I don’t give a damn what you think is obvious. Science is about looking at the data before coming to conclusions.” He was right. I was deeply impacted by my scientific training, so much so that by age 40 my agnostici …