"As you instructed, I am laying aside the issue of friends and family for the purposes of this question. 'Profound damage to my quality of life' would mean to me that the thing I lost could not be remediated or mitigated in any way. I might lose one of my limbs or senses and be more constrained in doing something that I loved, for example hiking in the back country, but there are workarounds - other senses, prosthetics, adaptations that might not give me exactly the same experience as before, but did close the gap on the loss. One could still consider this a profound loss, but I think I could overcome those deficits. In fact, no matter what loss I can name, we could apply this logic to it, and conclude that we could find a way to go on. Humans can bear almost any loss. Some of them have known such deprivation, whether through the condition of their birth or at the hands of some external event, that I hesitate to apply my first-world sensibilities to a question of what I could live without, because no matter what I choose, I can look around me and see someone living without that very thing. But given my relatively comfortable life and the resources available to me, my answer is that the one thing whose loss would profoundly damage the quality of my life would be the loss of my pets. I live alone, and while I have friends, colleagues and many contacts out in the world, my pets are always there with me, always ready to provide company, always needing my care, which it feels good to provide. Losing them would leave a stark, gaping hole in my life that I do not think could be filled by anything else. I would go on, somehow, of course. But my quality of life would be damaged. For how long, who could say? From where I sit right now, it would feel like a permanent, gnawing loss.

I am curious to know how you would answer this question, if you don't mind saying."