Right now, there are adult breadwinners who work full-time, or more than full-time, and still live in poverty. If the minimum wage in 1968 had simply kept up with inflation, it would be more than $10 today. If it also kept up with the added productivity of American workers since then, it would be more than $21 an hour. A decent society ensures that all workers get a decent wage. It’s the least we can do. And a $15 wage is the place to start.