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The Way Things Ought to Be

We often use the language of function to say something about how things should be, instead of just talking about how things are. Philosophers call this the distinction between the normative and the descriptive. If something has a function, we often think that it should fulfill that function – whether it in fact does so or not. If the function of the claw on a claw hammer is to grip nails for pulling, it should actually grip nails if used correctly. If it doesn’t do that, there’s something wrong with it. These are normative claims – claims about what is good or bad, right or wrong; about how things should or shouldn’t be. Ethical claims are normative, obviously, but not all normative claims are about ethical values. More on that later.

Photo credit: travelergeek via Unsplash

Scientists have often rejected teleological thinking. Science (it’s often been claimed) concerns itself with how things are, not with how they should be – with facts, not values. Science is in the business of giving an accurate description of the things it studies, not making normative claims about them. Yet, some scientists find themselves talking quite a lot about how things should or shouldn’t be. Health and disease, birth defects, transcription errors, invasive species, and ecological restoration, are all value-loaded concepts in scientific use.

One striking example comes from Antonio Guterres, the Secretary General of the UN. In his 2021 statement on the State of the Planet he summarized the message he was getting from scientists: “The state of the planet is broken.”

This seems to indicate a view of the planet that involves normativity. A broken planet is not as it should be. It also seems teleological: it suggests that the components of Earth have the purpose or goal of helping it to work as it should. Teleology and normativity thus go hand in hand.

Selected-Effects and Normativity

Does the selected-effects view of functions help make sense of how we think that there is a certain way some natural things “should” be? Perhaps.

To reiterate from a previous post, zebra stripes may prevent fly bites. If zebra stripes evolved because they protected stripey zebras from fly bites, that’s the “good” effect that the zebra’s stripes “should” have. But they might not actually have that effect. Maybe a zebra is born with stripes that are too wide, and flies are unaffected by them. Or maybe a new variety of fly has come along, one that is attracted by stripes. In cases like these, it seems like the stripes still have the function of protecting the zebras from fly bites, but they are not working as they should. Normativity seems to come along with teleology. But it’s hard not to feel that there is some sleight-of-hand involved here. You notice how many times I had to use scare quotes around the normative terms I just used – “should” and “good.” That marks the fact that these words are not being used in quite their normal senses, here, but in a more restricted way. The fly-repelling effect of stripes is certainly good for the zebras. But is that enough to say it’s good? Or that it’s what the stripes should do? Intuitions vary!

Later posts will demonstrate how normativity works with the other theories of function, namely, the causal-role view, the persistence view, and the organizational view.

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