I've had dogs my whole life, and the bond with my current Labrador is something I'd almost call spiritual—but I can't shake the question: do pets actually improve our mental and physical health, or are we just projecting human emotions onto animals that don't need us? Studies show lower blood pressure and reduced loneliness, but those correlations are messy; pet owners also tend to have higher incomes. Even if the science is fuzzy, I'd rather have the dog and the exercise routine he forces on me.