When the Mets traded for Mike Piazza, my son was 2 1/2. He grew up thinking that Mike Piazza was eternal- to him, he had always been there. When he outgrew a Piazza shirt, we got him a bigger one. When Mike finally departed in 2005, he was 10, and deeply rooted in his Met-ness. But it stung him that a part of his young childhood was suddenly gone. I knew Piazza had declined, that there was no room for him going forward. But my rational thinking was no match for the childish thought that some things should be permanent. It was his rough introduction to the fact that baseball is a business.