Even if you haven't got a green thumb, you can re-grow new plants from vegetable scraps simply by slicing the bottoms of celery stalks, bok choy and other greens, then sticking them upright in a shallow dish of water. For carrots and radishes and beets, it's the tops you lop off. Science says regeneration is natural. Cells have the ability to program a new stem, crown, clove— From the wilted lettuce, a young, vibrant leaf; a fresh new body you can harvest for next week's salad. Eventually, there must be a limit. You can't keep raising the dead forever; it would be too unnatural, improper. So I'm shocked to learn about the baseball player who apparently left instructions that upon his death, surgeons were to neuroseparate his head from his body. His head floats in a kind of dirty-looking thermos filled with liquid nitrogen, waiting for a future where our science would have advanced to such an edge that someone would know what to do to resuscitate the neurosuspended brain. Then it would sprout a whole new body, taut and strong and ready to swing a bat, sprint to base, sign a billion trading cards in a world we're not even sure will have the same greed we seem to have for stretching out life beyond life.