Philosophy Phriday: Do Ants Doubt?

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 fifty-ninth contribution in the series, submitted by Dr. Andrew Moon.

Do Ants Doubt?

Do ants doubt? I will argue that they probably don’t.

Some might think that ants don’t have doubts because they don’t have any mental states. They are just mindless robots.

Those people might be right. However, there are some reasons to think that ants do have mental states. Suppose an ant is walking along a path, and you put a Lego in front of it. The ant stops. If I said, “The ant knows that there is something in front of it,” this would seem like a correct thing to say. Or if I said, “The ant thinks that there is something in front of it,” that would also seem correct to say. In contrast, suppose you rolled a marble and it stopped because of the Lego in its path. If I said, “The marble knows/thinks there’s something in front of it,” this would be incorrect to say. The fact that we attribute knowledge and thinking to the ant (but not the marble) is some evidence that we categorize ants (but not marbles) into the group of things with minds.

An ant undoubtedly in doubt, or not. Photo: Alex Wild

Here is another example. Charles Gallistel (1990, 1) tells of the Tunisian desert ant, Cataglyphis bicolor, which “moves across the desert in tortuous loops, running first this way, then that, but gradually progressing ever farther away from the life-sustaining humidity of the nest.” After finding food, it “turns to orient to within one to two degrees of the straight line between itself and the nest entrance, a 1-millimeter-wide hole, 40 meters distant.” The ant then safely returns to its nest.  Gallistel attributes knowledge to the ant: knowledge of where to head and how far, as well as knowledge of its position relative to the nest. The fact that it seems right to attribute knowledge to such an ant is reason to think it does have knowledge.  But then the ant would have a mental state, and thereby, a mind.

If you are unconvinced, that’s okay. I’m not really convinced either. Perhaps we are just speaking loosely in these scenarios. Perhaps the ant knows things only in the same way that the door sensor at the grocery store knows that I am coming. There are a lot of interesting things to explore here, but that exploration would take us off track from the main topic of this article (see here, here, here, and here for further discussion of Cataglyphis in this series). So, from here on, I will instead argue that even if ants have knowledge and thoughts, they still probably don’t have doubts.

Why do I think this? Well, it’s because of my view about the nature of doubt. On my view, for you to have doubt, roughly, is for you to believe that you might be wrong. (More precisely, to have doubt that X is to think that it might be that not-X.)

Consider the mental states you have as you wake up and get ready for the day. You look at your alarm clock and see that it’s 8:00am; you think about a project you have due that day; you notice that you are hungry; you remember that it’s Tuesday. Your mental life is brimming with activity from the moment you awake; it involves seeing, thinking, noticing, and remembering. But so far, there is no doubt.

Suppose you then ask yourself, “Didn’t someone say that the project was due Wednesday and not Tuesday?” You then have the thought: my project might not be due today. It now seems that you have doubt that your project is due today. And lo, this is exactly what my view about doubt says. You don’t have doubt that the project is due today until you believe that the project might not be due today. This is because, on my view, that’s all it is to have doubt that the project is due today.

Let us return to the ant. It is one thing for an ant to think that there is food or that the nest is that way. But to think that there might not be food? To think that the nest might not be that way? It is very unlikely that it would have such thoughts. More generally, it is unlikely that an ant would have the more complex mental state of thinking that something might not be so. So, it’s unlikely that ants have doubts.

There are two ways to attack my argument. One is to attack my theory of doubt. Now, I devoted a whole journal article to defending my theory of doubt (see here for the unofficial but accessible penultimate draft). I think that, on the basis of that defense, it’s on pretty good grounds. However, philosophers have been wrong before, and I could be one of them.

The second way is to argue that ants do have thoughts about what might not be. The world is mysterious, nature surprises us, and perhaps ants have such complex thoughts after all. We should not underestimate ants! However, having thoughts of this complexity seems too much to expect, even from an ant. Still, this would be a second reasonable way to argue that ants, do, in fact, have doubts after all.



Gallistel, Charles 1990: The Organization of Learning. Cambridge, MA: MIT Press.

Moon, Andrew 2018: ‘The Nature of Doubt and a New Puzzle About Belief, Doubt, and Confidence’. Synthese, 195, pp. 1827–1848.

HeadShotDr. Andrew Moon is an assistant professor at Virginia Commonwealth University. His area of specialty is epistemology, and he has interests in philosophy of mind and philosophy of religion. Dr. Moon has recently published on the natures of belief and confidence, religious epistemology, memory, evidentialism, and evolutionary debunking arguments. He is also working on a book on the relationship between knowledge and the doxastic attitudes (belief, doubt, confidence, and certainty).