Training Log Archive: iansmith

I decided that I needed to go for a run, and I ran much more aggressively than I planned. Conditions were clear, 5 C, and fairly pleasant. While at 11 PM, there were still some people out on the streets, the density was sufficiently low that they were no inconvenience. I ran in a long-sleeved shirt, a short-sleeved shirt, tights, and gloves. I believe the heart rate spike near the beginning of my run was a recording anomaly.

I had much on my mind. Suppose we define happiness as some utility function on the space of possibilities available to us. I mused on the time dependence of those utility functions. We consider our immediate utility, e.g. when preventing ourselves from falling, or conforming to rigorous sleep and food schedules. Immediate discomfort has lower utility than immediate comfort. However, we also consider longer time scales - we maintain our bodies, we plan for the future, and we reflect on the long time scale ramifications of our decisions.

There exists a complex tradeoff between the different time scales. In college, e.g., the short term discomfort of sacrifice of sleep and the opportunity cost of time was an acceptable exchange for the longer term utility of completing assignments in pursuit of a degree. Conversely, short term comfort can outweigh long term utility, e.g. when someone reneges on a diet or chooses a break in lieu of work.

However, I cannot reconcile the following: any solution to an optimization will cease to be optimal because the utility function has parameters which fluctuate in time, particularly when longer time-scale components factor so heavily into our utility function. There is an underlying assumption that the rate of change of our utility function is slow, though I cannot now state this more precisely. I suppose both the short-term end and long-term ends of the time scales are stable utility regimes. That is, our fundamental short term requirements are unlikely to change, and our long term goals should be similarly stable, up to major paradigm shifts or life identity crises. Perhaps someone with more economic experience who has mused on these matters might comment?

Cool down run.