The Daily Ant hosts a weekly series, Philosophy Phridays, in which real philosophers share their thoughts at the intersection of ants and philosophy. This is the twenty-first contribution in the series, submitted by Dr. Lauren Ashwell.

Dispositions and Ant-idotes

Dispositions have seemed to some philosophers to be too spooky and other-worldly to be properties in their own right. Instead, these philosophers have tried to analyze dispositions away in terms they found more ontologically palatable. Dispositional ascriptions, it was once thought, are really just assertions of counterfactuals connecting stimulus conditions to manifestation conditions: to say that something is soluble in water is just to say that it would dissolve if it were placed in water, to say that something is flammable is just to say that it would burn if an ignition source were applied, and to say that something is poisonous is just to say that it would harm you if you were exposed to it [i].


This fire ant is very disposed to hurt you. Photo: Alex Wild

However, this kind of simple counterfactual analysis came under challenge from several types of counterexample. One such counterexample involves antidotes: something may be poisonous to a potential victim, even though it would not harm that potential victim because they have an antidote on hand. A particularly interesting kind of antidote is used by the Tawny Crazy Ant (Nylanderia fulva) when it is attacked by the Red Fire Ant (Solenopsis invicta). Many ant species use formic acid as a weapon against threats and to subdue prey; the Tawny Crazy Ant, however, has an additional use for this acid: when attacked by Fire Ants, the Tawny Crazy Ant rubs its own formic acid over its body to counteract the Fire Ant venom. Without this protective measure, the Tawny Crazy Ant has only a 48% chance of surviving a Fire Ant attack. With the application of the formic acid antidote, the chance of survival rises to 98% [ii].

If the simple counterfactual analysis of dispositional ascriptions were correct, then we would have to conclude that the Fire Ant venom is not poisonous to those Tawny Crazy Ants who in fact apply the formic acid. But if poisonousness is intrinsic [iii], as many dispositional properties seem to be, then we run into a problem. Suppose some group of Tawny Crazy Ants is prevented from applying the formic acid – perhaps they are temporarily stuck in sidewalk chewing gum and are unable to rub their protective antidote over themselves when attacked. Many of these ants would die if attacked by Fire Ants, and the ones that survive would be badly harmed. Thus the counterfactual “if they are exposed to Fire Ant venom, then they would be harmed” is true, and by the simple counterfactual analysis, Fire Ant venom is poisonous to these Tawny Crazy Ants. So unless poisonousness to Tawny Crazy Ants is extrinsic, the simple counterfactual analysis cannot be true.

So the Tawny Crazy Ants’ use of the formic acid antidote is a good counterexample to the simple counterfactual analysis of dispositional ascriptions, on the assumption that poisonousness is intrinsic. But even more interestingly, it also might provide us with an example of intrinsic dispositional interference. While dispositional interference from something separate from the disposition bearer – as the formic acid antidote is separate and extrinsic from the Fire Ant’s venom – is quite widely accepted by metaphysicians, it is more controversial whether dispositions can be prevented from manifesting by other intrinsic features of the disposition bearer [iv]. The possibility of intrinsic dispositional interference is important for, among other things, how we might understand mental states, particularly desires, in terms of dispositions [v].


A crazy ant, grateful that Dr. Ashwell included her! Photo: Alex Wild

Note that, generally, the manifestation of dispositional properties requires pairs of dispositions – the fragility of the glass requires the hardness of the ground to manifest breaking. Similarly, the poisonousness of the Fire Ant venom requires the vulnerability of the Tawny Crazy Ants. Returning to our unfortunate chewing-gum-restrained group of ants, we can clearly see that they are vulnerable to the venom. If vulnerability to Fire Ant venom is intrinsic, then the free Tawny Crazy Ants are also vulnerable. However, when free, they utilize their own formic acid antidote to prevent harm to themselves. The formic acid is intrinsic to the Tawny Crazy Ant, and, when applied, prevents the manifestation of their vulnerability to Fire Ant venom – that is, it seems to be a case of intrinsic dispositional interference.

Now there are few possible replies one might make to this argument. One might question, as Jennifer McKitrick has, whether vulnerability is in fact an intrinsic property [vi]. Whether a rabbit, for example, is vulnerable, might depend on what other critters there are in the environment – are there foxes? People with guns? If there are no threats, then you might conclude that the rabbit isn’t vulnerable. Note, though, that this observation doesn’t challenge my example – the rabbits, even when there are no foxes or other threats, still have the dispositional property of being vulnerable-to-larger-animals-with-sharp-teeth, even when there are none in the environment. The kind of vulnerability involved in my example is vulnerability to a kind of poison, which things may have even in the absence of that poison.

In thinking about dispositions, we need to be careful which object we are attributing the disposition to. One might question whether the rabbit would be vulnerable if the rabbit were wearing body armor – it would certainly then be less likely to be harmed. However, the rabbit itself would still be vulnerable, even though the compound object consisting of rabbit+body-armor is not vulnerable. After all, the rabbit’s vulnerability seems to explain why it needs the body armor. Similarly, the Tawny Crazy Ant’s vulnerability to Fire Ant venom seems to explain why it needs to rub the protective formic acid over itself; the difference, however, is that while the rabbit’s body armor is extrinsic, the formic acid is intrinsic to the Tawny Crazy Ant.

That said, one might question whether the formic acid antidote really is intrinsic to the Tawny Crazy Ant. It is true that being internally located isn’t exactly the same thing as being intrinsic – a balloon may be filled with water, but this does not make the water intrinsic to the balloon. If the formic acid is held within the body, it may be internal but not intrinsic – and if it is not intrinsic, then it the activity of applying the formic acid as a protection is not an intrinsic dispositional interference. But imagine the formic acid is produced at the last minute, from ingredients that aren’t just held internally but that in fact constitute parts of the ant’s body. Then it would be hard to argue that the formic acid is extrinsic. And whether the formic acid is held internally or made in this way seems like it ought not to make a difference to whether the Tawny Crazy Ant is vulnerable to Fire Ant venom or not.


Is this biologist vulnerable to bullet ant stings? Who knows! Photo: Alex Wild

Lastly, one might question whether the operative antidote is the formic acid, or instead the ability to apply the formic acid – and also question whether this ability is really intrinsic. One might argue that the ants-in-gum lack the ability to apply their own formic acid, due to their extrinsic situation (being stuck in gum). If this is correct, then the thing that prevents the Tawny Crazy Ants’ vulnerability from manifesting, when they do protect themselves, is not intrinsic – it is the extrinsically dependent ability to apply the formic acid. This, however, depends on what you think about whether abilities can be had even when we are prevented from exhibiting them, as dispositions can be [vii]. Do we really lose abilities so easily when temporarily inhibited? Although there is some counterfactual sense in which the ant-in-gum cannot deploy its protective antidote, a robust understanding of abilities should still accept that it has the relevant ability – the ant is just temporarily extrinsically prevented from manifesting the ability, in much the same way that dispositional properties can be had even though they are, or would be, extrinsically (and, I would argue, sometimes intrinsically) prevented from manifesting.


[i] Although I need something more specific than “harm” and “exposed” here, I hope you will bear with me.

[ii] E. G. LeBrun, N.T. Jones, and L.E. Gilbert (2014). Chemical warfare among invaders: a detoxification interaction facilitates an ant invasion. Science, 343(6174):1014-1017.

[iii] A property is intrinsic, roughly, if an object’s having that property depends only on how it is in itself, and not on how the world is outside the object. Relational properties, when they involve relations to things outside of the object, are extrinsic. Although our way of specifying poisonousness involves a relation – strictly speaking, the kind of poisonousness we’re interested in is poisonousness to a particular kind of creature – this does not yet make it extrinsic. Being poisonousness to a particular kind of creature is a property that something can have even if that kind of creature does not in fact exist – it doesn’t require an actual extrinsic relation to hold.

[iv] For some arguments for the possibility of intrinsic dispositional interference, see: Lauren Ashwell (2010). Superficial Dispositionalism. Australasian Journal of Philosophy, 88(4): 635-653; Randolph Clarke (2007). Intrinsic Finks. The Philosophical Quarterly 58: 512–518. For some examples of appeals to the idea that intrinsic dispositional interference is impossible, see: Sungho Choi (2005). Do Categorical Ascriptions Entail Counterfactual Conditionals? The Philosophical Quarterly 55: 495–503; Toby Handfield (2008). Unfinkable Dispositions. Synthese 160: 297-308. Daniel Cohen and Toby Handfield (2007). Finking Frankfurt. Philosophical Studies 135: 363-374; Toby Handfield and Alexander Bird (2008). Dispositions, Rules and Finks. Philosophical Studies 140: 285-298. As Randolph Clarke (2007) notes, the view that intrinsic dispositional intereference is impossible is widespread, though not necessarily explicitly endorsed in publication.

[v] Lauren Ashwell (2017). Conflicts of Desire: Dispositions and the Metaphysics of Mind. In Causal Powers, ed. by Jonathan Jacobs, Oxford University Press, 167-176.

[vi] Jennifer McKitrick (2003). A Case for Extrinsic Dispositions. Australasian Journal of Philosophy, 81(2): 155-174

[vii] Michael Fara (2008). Masked Abilities and Compatibilism. Mind, 117: 843-865.

LaurenAshwellDr. Lauren Ashwell is an Associate Professor in the department of philosophy at Bates College, Maine. Her areas of specialization are feminist philosophy, metaphysics (especially dispositions), philosophy of mind (especially desires), epistemology (especially self-knowledge), and philosophy of muppets. She originally hails from New Zealand, where there are fewer poisonous ants (and muppet ants) than in the US.