I'm not sure how the mind selects the memories it retains, but I do know that when I think of Roy Halladay, the image that appears is from an April afternoon in 2010. This was before the perfect game in Miami, before the no-hitter in the postseason, before any of the exploits that would come to define the final chapter of one of baseball's greatest pitching careers. In fact, this was the afternoon of Halladay's first regular-season start in a Phillies uniform, an 11-1 victory in which he struck out nine and allowed one run while throwing just 88 pitches in seven innings of work.

An hour or so after the end of the game, Halladay emerged from the visitor's clubhouse at Nationals Park wearing street clothes and that same steely expression you saw on his face each time he glared down his brim toward home. At the time, I still had not figured out what, exactly, to make of the guy. I'm sure that I'd seen him smile at least once or twice during the month-and-a-half I'd spent covering the Phillies in Clearwater that spring, but any personality he possessed had remained buried beneath the no-nonsense demeanor with which he attacked his daily work. He was an intimidating presence, in part because greatness is always intimidating, but more so because of that deadly sincerity that seemed to consume him.

Everything Halladay did seemed to have a purpose behind it. When he walked through the clubhouse, it was because he was on his way to do something, and whatever that something was, you could be sure he was doing it with the intent of putting himself in a position to dominate opposing hitters. One of the characteristics that separates the greats from us mortals is the singularity of their focus. With Halladay, that focus never seemed to fade, whether he was pulling into the parking lot with his headlights on for the start of another day, or leafing through the notebook in which he logged the batters he faced, or returning from the workout he put himself through after each one of his starts. You saw that singularity, and, at times, you wondered what kind of human lurked beneath it.

Then came that April afternoon: As Halladay stepped out of the clubhouse and into the cement concourse that borders the playing surface at Nationals Park, his gaze settled on a trio of people waiting off to the side: They saw him and shuffled over, a woman and two boys, their actions animated by an excitement peculiar to husbands and fathers at the end of a shift. Halladay opened his arms, bent down toward the ground, and, planted a kiss on one of his sons' lips. As he did this, his face erupted in a smile that I can only describe as one of the warmest, most genuine displays of emotion that I have ever seen in such a setting. In that moment, the circle of dirt that defined his existence seemed a million miles away.

In the years since, the thought of that smile has crossed my mind on a number of occasions. One of those instances occurred in the winter of 2013, when Halladay walked into a hotel ballroom and announced his retirement from the game he'd spent most of the previous decade dominating. The four seasons that Halladay spent in Philadelphia offered us no shortage of memories. On the mound, he was the most consistently dominant pitcher that members of my generation have ever seen. Off of it, he was a living testament to the ferocity of the human will. If everybody prepared themselves for their jobs the way Halladay prepared himself for his, the world would look a lot different than it does today.

Yet there was always something deeper with Halladay, and it was in those subtler moments that it shined. What struck me about that final press conference was how content he'd seemed. He talked of fish to catch and books to read and youth baseball teams to coach. I suppose that when you pour all of yourself into an endeavor, it is easy to recognize when you have nothing left to give. Listening to him talk, I thought about that moment after his first start as a Phillie, and I realized how much sense it made.

Another time I thought of this was Tuesday afternoon. The news fell like the cold rain: a plane down in the Gulf of Mexico, the numbers on its tail matching those on his social-media feed. Roy Halladay: husband, father, pitcher, dead at 40.

Rarely do we know our athletes as well as we think that we do. Human beings are complex creatures, even the ones we see on TV. But the four years I spent watching Halladay go about his business leaves me with no hesitation. Here lies one of the good ones. May he rest in peace.