The meaning of life

An essential difference between the perspectives of public health and medicine lies in their ethical foundations. Although broader considerations have begun to infiltrate medical ethics, physicians generally understand that they have an absolute obligation to the individual patient. That is what most of us want from our own doctors, and it is how most people believe doctors ought to behave. When an individual in desperate straits lies before us, we (most of us, anyway) instinctively want to strain every sinew, spend every penny, bend or break every rule, to save them.

This is called the Rule of Rescue, which I have discussed before and yet again. (And a few more times after that.) But public health addresses human welfare at the level of the population, not the individual, and here a conflict inevitably arises.

How much is a human life worth? Most people immediately respond, without even thinking about, that every human life is infinitely precious and it is offensive to put a dollar value on human life. But that answer is feckless. In the first place, we do not have infinite resources. And obviously, we do not spend even a small fraction of the resources we do have to extend the lives of people we could easily save, including four thousand or more young children who die every day from readily preventable causes such as contaminated water, malaria, hunger or violence. Indeed, the U.S. government expends vastly more resources to kill people than it does to save the lives of those children, while some of the very people who insist on the sanctity of all human life, including lives (or even what may be non-living entities) that many people don't even define as human, are among those who cheer the loudest.

And yet, responding to the rule of rescue, we expend hundreds of thousands of dollars to extend the lives of very sick people, even when they are very old, and most people consider it outrageous and immoral even to question this -- even when you point out that most people on earth don't have the benefit of these expensive technologies.

In public health, we know better. We know we have to try to develop some metrics for comparing the value of lives with the cost of resources, and we need to develop ethical principles for allocating resources in relation to lives. We also know that it is impossible to save anyone's life, because everybody dies -- and that starts early. At least a third of human embryos are spontaneously aborted. God is by far the most prolific abortionist and mass murderer -- no human being can ever come close. Human life may be precious to somebody or something, but it isn't worth shit to God.

In fact, if you take the trouble to ask people, it turns out they don't even think their own lives are infinitely precious. One metric that is often used in public health is the Quality Adjusted Life Year (QALY). You calculate that by first doing a large-scale survey and asking people how much life span they would give up to avoid a year of being, for example, totally bedridden, or wracked with arthritis pain. It turns out that nearly ever one is willing to trade some total time spent living to avoid some time spent living in unpleasant circumstances. (Most of us, obviously, don't even want to persist for one minute in a vegetative state, without hope of recovery. What would be the point?) You can take the average of responses to these sorts of questions to calculate the payoff for medical or public health interventions, including those that don't necessarily extend life, but promote health and prevent disability and pain. As a matter of fact, most people would even accept a large sum of money today in exchange for some weeks or months lost at the end of life. So you can put a monetary value on life after all. Some people even risk their lives intentionally just for a thrill, and we take a chance of dying every time we drive to the grocery store -- a chance which we are aware exists, even if we haven't consciously calculated it.

When we sit down and think about how best to allocate resources in order to maximize the values that people associate with human life, we inevitably end up with a rule of justice, not a rule of rescue. We get by far the biggest bang by concentrating on the least fortunate -- although admittedly only if we start after the fetus is well on its way, and by placing the terminally unconscious outside of our universe. Taking care of basic needs of poor children -- and the poorer the better, in terms of results -- and their families, offers by far the biggest payoff. And reducing social inequality in the first place has a double effect. Even without directly addressing health risks and health care needs, it improves the overall level of population health.

Next it makes sense to tackle pervasive health risks, which are often distributed inequitably but aren't specifically tied to poverty. These include tobacco, environmental contamination, violence, and other human-caused hazards. Why do these persist when we know what they are and how to fix them? Because some people benefit from them. The risks from natural disasters also fall disproportionately on the poor, which is why we don't invest enough to mitigate them. And so on.

In short, public health, no matter where you start from, leads you inevitably to social justice. Justice makes our species better off.