Memory
- for Xu Liu, my dear friend and mentor
Memory works in the weirdest of ways, as Xu would know best. For the past week, since I heard about Xu's passing, pieces of memory sneaked into my every day as they never have before.
I first got to know Xu just a little over six years ago in a class on memory, which has been Xu's focus of research ever since. I used to joke with Xu that I could be his test subject: in his quest to understand memory, he could just study why my memory is so bad, the same way people study how a gene works in a mutant mouse missing the gene. I told him I think that this is my secret ingredient to a happy life, having a bad memory allows me to live like a child, beginning every day as a fresh and curious one. My "glass-half-full" genes get to express to their hearts' content without the potent inhibitor that is "the past". But this past week has been different: then and there weave seamlessly into now and here. All the dormant memories of moments I shared with Xu awoke.
When I walk by Bostonians hard at work shoveling their cars out of the historic snow storm, I remember the winter where I parked my car next to Xu's. He laughed at how his car was snowed in and shoveled out so many times, while I just left mine there untouched until when spring melts away all the snow, as if nothing happened. It was also that winter he volunteered to take care of other friends' cars when they were abroad. When I go to lab to do a mouse surgery, I remember how we shared tips on how to secure brain implants. When I was presenting my work in front of my thesis committee last week, I remembered when we talked about how crucial it is to do double-blinded behavior assays. On my walk home I passed by the crepe store where I shared a long conversation with Xu. We would only meet once every few months over dinner, but every time we got together, we would have long chats about life, science, our shared fascination with nature and all her secrets. It was the kind of conversation that nourishes me deep within. I always walked away with firmer strides, while humming my favorite tune. I didn't realize just how incredibly lucky I was to have a friend, a mentor, someone who I could talk to on the path to pursue the truth, making this journey a little less lonely.
Since Xu got an offer to start his own lab, our conversations shifted to how he would find good people to join his lab and how he would craft new research projects. I came to appreciate the immense pressure associated with being a junior professor starting a new research enterprise, and I remember telling Xu that whoever works in his lab will be so lucky to have him as a mentor. In the end of January, Xu drove to Chicago with a car full of hope to start his next adventure. I teased him that he chose the coldest month to move to the coldest city. He laughed and said that it was the right way to do it, because it would only get warmer from then on.
Xu was always the reason why I believe if we do good, we will end up somewhere good. He gave me the faith that in a gentle and elegant way, through curiosity, hard work, resilience, and maybe a little luck, one can do good and meaningful work. Every time our paths crossed, I walked away with lots of positive energy. Reading through notes left by other friends of Xu, I realized I was not the only one. Even though I don't recognize many names of Xu's friends, I feel as if we were all connected and luckily inducted into a secret club, where we got to know and be inspired by Xu. Oliver Sacks writes this week, that "When people die, they cannot be replaced. They leave holes that cannot be filled, for it is the fate — the genetic and neural fate — of every human being to be a unique individual, to find his own path, to live his own life, to die his own death." Now, Xu's family, friends and I will live with this hole, but for me, it will be permanently filled with happy memories of Xu. Oliver Sacks continued: "I have been a sentient being, a thinking animal, on this beautiful planet, and that life itself has been an enormous privilege and adventure." I'd like to believe that likewise Xu has left without much regret, because he has lived his life with so much respect, seriousness and compassion by doing everything and treating everyone with care and devotion. I'd also like to believe that life has treated him with much respect in return.
Xu, I want you to know that as I remember you, whether sitting on a shuttle bus crossing the Charles River, or treading through the snowy Mass Ave, I have tears in my eyes, but a smile on my face: I know I will keep you in my memory and live on, only stronger, more bravely and deeply. In this most precious adventure that is life, I will take care of myself and my loved ones, and work the way you would. I will walk around feeling the positive energy from you. Xu devoted his life to studying memory, and he figured out how to "implant" memory into mice, but what he has excelled in, is to give all of us fortunate to know him memories that would last.