Bitterness and Food Rejection

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Bitterness and Food Rejection

step 1

change the question

Greene et al’s question:

‘We developed this theory in response to a long-standing philosophical puzzle known as the trolley problem’

(Greene, 2015, p. 203; see Greene, 2023)

problem: there are confounds.

Which factors influence responses to dilemmas?

Waldmann, Nagel, & Wiegmann (2012, p. 288) offers a brief summary of some factors which have been considered to influence including:

- whether an agent is part of the danger or a bystander;

- whether an action involves forceful contact with a victim;

- whether an action targets an object or the victim;

- how the victim is described (Waldmann et al., 2012).

- whether there are irrelevant alternatives (Wiegmann, Horvath, & Meyer, 2020);

- order of presentation (Schwitzgebel & Cushman, 2015);

Wiegmann et al. (2020) show that they are subject to irrelevant additional options: like lay people, philosophers will more readily endorsing killing one person to save nine when given five alternatives than when given six alternatives. (These authors also demonstrate order-of-presentation effects.) This is not mentioned in Waldmann et al. (2012, p. 288)

‘almost all these confounding factors influence judgments, along with a number of others’

(Waldmann et al., 2012, pp. 288–90).

Given this, it is hard to make predictions about how time pressure might skew judgements.

‘almost all these confounding factors influence judgments, along with a number of others [...] The research suggests that various moral and nonmoral factors interact in the generation of moral judgments about dilemmas’

(Waldmann et al., 2012, pp. 288–90).

I might be wrong about this. Greene offers a spirited defense in his 2023 paper (Greene, 2023), although this does not mention Waldmann et al. (2012) and I don’t recall there being a discussion of confounds.

My sense is that trolley dilemmas might be useful in many ways, but I also think we should not stake so much on them

ASIDE: Interesting to think about cases where these dilemmas may have arisen.

They are supposed to show side effects of general ethical principles.

But Waldman’s conclusion indicates that they are not doing this.

How would such a dilemma have arisen in evolutionary history? Plausible cases are (i) filial infanticide (Hrdy, 1979), and (ii) killing for the purposes of nutritional cannibalism in times of famine. (I am assuming nutritional cannibalism is linked to famine because humans are not a great source of nutrition (Garn & Block, 1970). There also seems to be evidence (∞todo: where do I see this) that hominins could mostly have found more nutritional sources that were easier to kill, so nutritional canibalism would have been unmotivated (but see Rodríguez, Guillermo, & Ana (2019) who argue that nutritional cannibalism was significant because (i) hominins mostly ate already dead hominins, and (ii) these were relatively were easy to get hold of as they were your mates).) (on evidence that we may have experienced famine, see fig2 of Foerster et al. (2022) on climate stability to ~300kya then instability at Chew Bahir in Ethiopia).

On (i), filial infanticide. Seems like there is a clear yes, do it.

On (ii), nutritional cannibalism, do you think that we have ethical abilities which guide you on when to eat someone?

Think about ethical concerns with purity. Stress the body enough and my guess is that these go out of the window. Ethical abilities are designed to operate when things are going well, and to stop when your body is under extreme pressure.

Think about starvation for a moment. Your body will reduce the calories it burns, prioritizing essential things like your heart, brain and kidneys over optional extras like your muscles, skin and hair. (O’Keefe, 2015, pp. 9–10). And your sex drive will all but disappear (Benedict, 1919, p. 639ff). It would be a bit odd to keep the ethical functions operating in these circumstances. (The obvious one to think about here is purity: do you want to be concerned with purity while starving?)

Objection: participants given the dilemma are not starving, and they do have an evolutionary ability not to kill conspecifics. This is all Greene et al are banking on: the prohibition on killing will shine through.

Reply: prohibition on killing probably only applies to in-group members.

Anyway, this is why I started with an alternative question

I am not sure this is a good question to start with.

alternative question

What is the relation between
ethical attitudes
and
the behaviours which they sometimes but not always control?

step 2

distinguish ethical abilities

Greene et al offer a theory of ethical cognition quite generally. My suggestion is that we probably need to think about the problem in smaller chunks.

Thus the fast processes which explain cooperation, say, might not have a lot in common with those that explain impurity, say.

Greene et al’s assumption:

‘morality is a suite of cognitive mechanisms that enable otherwise selfish individuals to reap the benefits of cooperation.’

(Greene, 2015, p. 198)

I think ethical abilities have a variety of different functions. For example, abilities linked to purity are clearly related to avoiding pathogens, as we will see in a moment. This does all not boil down to cooperation.

(I’m also not persuaded that ethical abilities make us less selfish.)

These abilties include care, cooperation, inequality aversion, and more.

ethical abilities

- care

- cooperation (Boyd & Richerson, 2022)

- inequality aversion (Brosnan & Waal, 2014)

- balance authority vs autonomy (Wengrow & Graeber, 2018)

Wengrow & Graeber (2018) describe two groups, one of which eschewed slavery, the other of which used it in a complex hierarchical society.

‘If the ethics of their Californian neighbors bore comparison with mercantile values in early modern Europe, those of the Northwest Coast more closely resembled the aristocratic values of high feudalism. Societies comprised household estates divided into hereditary ranks of nobles, commoners, and slaves. Slaveholding was a defining attribute of nobility , and from Alaska south to W ashington state, intergroup slave raids were endemic. Nobles alone enjoyed the ritual prerogative of engaging with guardian spirits who conferred access to prestigious titles, which defined the legal contents of an estate. Commoners voluntarily provided labor and services to noble kin, who vied for their allegiance by offering spectacular feasts, entertainment, and the pleasure of vicarious participation in heroic exploits.’ (Wengrow & Graeber, 2018, p. 239)

- discern impurity (Chakroff, Russell, Piazza, & Young, 2017)

Also (Atari et al., 2022) on impurity (but that comes later)

- ...

For today, I am going to focus just on impurity. (Of course this is a major limit—it’s unlikely that any theory we construct here will generalise to other ethical abilities.)

Many people here are likely to think of ethics in terms of harm and fairness only. But in many cultures purity is an important area of concern.

Impure acts come in many kinds: there are sexually impure acts (using a chicken carcas for sexual pleasure, say); there is the scatological domain; there are acts of cannibalism, and much more.

I started with the example of vommiting oversomeone and then eating your own vomit partly because this is a paradigm impure act.

step 3

find a non-ethical model

What I want is a case in which there is decoupling between attitudes and behaviours, and that is extremely well understood.

food-rejection behaviours

I want to start by considering an analogy with food-rejection behaviours.

problem: need nutrients / risk poisons

All animals, but especially herbivores, face a trade-off between getting enough to eat and ingesting poisons. They therefore exhibit a sophisticated variety of food-rejection behaviours.

Food-rejection behaviours in humans are a very well-understood case of decoupling. That is, food rejection can occur independently of attitudes about toxicity, and even contrary to them (as when you just cannot bring yourself to swallow a bitter pill).

slow: toxicity judgements

In humans, of course many of these behaviours are driven by judgements about toxicity. If I know the sandwiches have been left in the sun for a few hours, I'll probably give them a miss.

But judgements about toxicity are slow and not always reliable. There is a much faster process which also plays a role in food rejection, and this is one that humans share with a very wide range of animals ...

fast: aversion to bitterness

This is aversion to bitterness.

Although the correlation between bitterness and toxicity is not super strong and bitter things can be beneficial (such as caffeine, for example), there is broad consensus that avoiding poisons is one of the functions of sensitivity to bitterness (Nissim, Dagan-Wiener, & Niv, 2017). Animals who encounter a greater proportion of poisonous foods in their normal diet (herbivores) show both higher sensitivity to bitterness (Li & Zhang, 2014) and a higher tolerance for it (Ji, 1994). This makes sense because herbivores need to take more risks: they could not get enough to eat if they rejected everything bitter. Further, two changes in diet which reduce exposure to toxins, namely eating more animals or cooking with fire, may have gradually reduced sensitivity to bitterness (Wang, Thomas, & Zhang, 2004).

To get a sense of how basic this process is, let me return to the sea anenomes ...

You can habituate sea anemones to a diet of gellatine capsules, which they happily eat. But suppose you make one bitter and then feed it. The sea anenome will immediately eject it and henceforth refuse those capsules (Garcia & Hankins, 1975).

A range of animals including sea anemones become averse to a food type after a single bitter encounter (Garcia & Hankins, 1975). In rats, ‘[t]he modal elicitor of aversive behaviours is a bitter, normally avoided substance like quinine, which evokes chin rubs, gapes, face washes, forelimb flails, and paw treads’ (Forestell & LoLordo, 2003, p. 141; Grill & Norgren, 1978; see Figure below). And in humans mixing a neutral flavour (vanilla, for example) with a bitter substance can reduce liking for that flavour (Baeyens, Crombez, De Houwer, & Eelen, 1996; Dickinson & Brown, 2007).

[SKIP THIS—NOT USING THE COMPLEXITY]

Useful to clarify what is meant by ‘bitterness’ here. Not suggesting that sea anenomes need sensation. Instead they have receptors which bind to molecules that in humans give rise to a sensation of bitterness.

Interesting story: bitterness works on at least two levels. One is relatively automatic and does not require sensation at all; and is linked to learning.

Second level is that, in humans and probably in other animals too, which almost certainly include chimpanzees (as they can use for medicine), the various receptors each give rise to a bitter sensation. The sensation can then be interpreted and used to avoid toxins.

Importantly none of this requires attitudes to toxicity, nor even any awareness of posion as a possibility.

This is important: when we talk loosely about bitterness driving food rejection, there are a range of things we might mean. It could be that receptors trigger aversion, which may support learning; or it could be that there is a sensation which modulates behaviours.

So food-rejection provides quite a bit of complexity that will be useful in thinking about purity.

[old way] It will be useful to note that ‘bitterness’ can refer to two things. In humans and other animals, there is a sensation of bitterness; we say that things taste bitter, for example. And we might decide what to do on the basis of that sensation. (Can use bitter-taste to discover medicines; indeed, that appears to have been important historically in aurevedic medicine, and there are also examples of this in other animals including chimpanzees.)

But in the case of the sea anenome, we are not committing to there being any sensation. Instead there are receptors which respond to a range of molecules that in humans are associated with the bitter sensation.

disanalogy: bitterness vs disgust

I don’t want to push this too far. Disgust is unlike bitterness in many ways. In particular, bitterness has its roots in the ability to detect particular molecules which correlate with poisons; I am not suggesting that disgust works like this at all.

Disgust also has social aspects: what is disgusting probably depends from culture to culture.

And there are plausibly many things that get called ‘disgust’, some more visceral and some that are merely attitudes (and perhaps some which combine bodily sensations with attitudes—who knows?).

But we have a worse problem ...

objection: it’s not intrinsically ethical

You have a purity-related behaviour that is driven by disgust. It looks ethical because we philosophers, who are observing it, make ethical judgements about it. But this is a merely external perspective. Taken on its own terms, the behaviour is no more ethical than is the food-rejection behaviour.

Constrast Greene et al’s view. This was not a problem for Greene et al’s view: if the fast process computes deontological rules, then there is a clear sense in which we have ethical behaviours.

This is important to me—it’s not enough that it looks ethical from my point of view as an outsider. After all, I have quite strong views about filial infanticide and nutritional cannibalism; but I do not think that these should apply to a million years or so of human history.

Now I don’t know much about ethics at all, so I checked the Stanford Encyclopedia ...

‘When it comes to morality, the most basic issue concerns our capacity for normative guidance: our ability to be motivated by norms of behavior ...’

(FitzPatrick, 2021)

I hope this makes the problem clear.

If you avoid doing something because you find it disgusting, there is nothing obviously normative about that.

normative guidance. The problem is that this seems to take us in a circle: it would seem that normative guidance demands normative attitudes. But our whole idea was to explain *ethical decoupling*!

How can there be normative guidance without normative attitudes?

So the challenge we face now is to build on the model of food-rejection behaviours so that we get something intrinsically ethical.

step 4

borrow an idea about normativity

minimal norm

- a pattern of behaviour

which exists in part because of others’ responses to behaviors which conform to, or violate, the pattern;

where these responses have the purpose of upholding conformity to the pattern.

Can be understood in terms of intention, but can also be understood teleologically.

To illustrate, disgust may cause you sanction someone who avoidably vomits all over you by, for example, shunning them as a cooperation partner. Suppose this is entirely unreflective on your part, a simple matter of disgust. Nevertheless, there may be a teleological sense in which this shunning has the purpose of holding up the do-not-vomit-on-people pattern of behaviour.

Another possible way of making the notion of purpose more precise: you have been trained by others around you to respond to some category of behaviour by being disgusted; and this training has the purpose of upholding a pattern of not performing behaviours in that category.

So the notion of a minimal norm provides us with a useful sense in which there can be normative guidance without normative attitudes.

KEY: normative guidance without normative attitudes

objection (recap): disgust-driven behaviours are not intrinsically ethical

reply: disgust can underpin purity-related minimal norms independently of normative attitudes.

purity

slow process

driven by purity judgements

fast process

disgust underpins purity-related minimal norms

There is not really a fast process here at all.

conclusion

In conclusion, ...

What is the relation between
ethical attitudes and
the behaviours which they sometimes but not always control?

thesis: 
(i) disgust can can underpin purity-related minimal norms independently of normative attitudes; and
(ii) this is one reason why ethical decoupling occurs.
predictions (~): 
(i) learned disgust can give rise to minimal norms; and
(ii) the minimal norms can outlive changes in ethical attitude.
Do not have proper predictions yet ...
Is it possible to induce disgust at an arbitrary feature
of an alien species (blue people vs orange people—one does lots of
disgusting things and you are told that these are dangerous
transmitters of all kinds of disease)?
Would this result in minimal norms?
And suppose you later provided participants with new information showing that
they had been entirely misled about the orange people, because in their
environment the baceria are different and these actions,
far from being dangerous, are actually beneficial.
Would participants now persist in implementing the minimal norm?

bkg img source: bing AI

terminology: ethical decoupling

As I use the term, *ethical decoupling* occurs when behaviours with ethical significance such as caring for another, cooperating, are not under the control of ethical attitudes. (The behaviours may, but need not, conflict with ethical attitudes.)

What is the relation between
ethical attitudes
and
the behaviours which they sometimes but not always control?

challenge: characterise the processes, and the behaviours

limits
(i) only one domain (purity); and
(ii) the thesis merely restate some old ideas.

E.g. this is bits of Haidt et al (except that there’s a bigger role for reason)

Greene et alDisgust + Minimal Norms
characterises cognitive aspect of processes✓~
characterises what processes compute✓~
the processes are distinctively ethical✓✓
theoretically motivated~✓
generates predictions✓~
predictions confirmed𐄂??

	Greene et al	Disgust + Minimal Norms
characterises cognitive aspect of processes	✓	~
characterises what processes compute	✓	~
the processes are distinctively ethical	✓	✓
theoretically motivated	~	✓
generates predictions	✓	~
predictions confirmed	𐄂	??

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Bitterness and Food Rejection

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