The source of all food

I once worked with a group of inner city kids in D.C. some of whom believed that the source of food was cans. Why would they believe otherwise having grown up in a completely concrete environment? There’s no evidence there that points to anything else. But how many people really think about or, better yet, know the source of their food? Soil is the source of all of our food, whether grown in city or country, and if food isn’t grown in well prepared, friable soil then we are not eating nutritious, nurturing food whether it is organic or not.