Your complimentary articles

You’ve read one of your four complimentary articles for this month.

You can read four articles free per month. To have complete access to the thousands of philosophy articles on this site, please

SUBSCRIBE NOW

Tallis in Wonderland

The Possibility-Bearing Animal

Raymond Tallis explores a twilight zone.

There have been many ways in which philosophers have tried to characterise our distinctive human nature, and some are more convincing than others. Aristotle’s definition of man as ‘the rational animal’ invites wild laughter in the light of what we often get up to individually and collectively. Perhaps ‘the rationalising animal’ may be closer to the mark, given our capacity to justify the most destructive, counter-productive, and wicked behaviour. Homo sapiens – the title science has conferred on our most recent edition – which translates as ‘wise man’, also seems open to challenge, given that our wisdom, such as it is, is manifested somewhat intermittently.

The definition of man as ‘the speaking animal’ is less vulnerable. We are, after all, (possibly) the only living creatures who can communicate abstract ideas by means of abstract symbols materialized in hot air – and, more recently, black ink. Out of such communication, in which what-is is made explicit and transformed into ‘that-it-is’, we have woven the infinitely complex world in which we pass our lives. This is the realm to which I have applied an ugly neologism: the Thatosphere (see my Seeing Ourselves: Reclaiming Humanity from God and Science, 2020). Being comprised of shared knowledge and expectations, institutions, practices, and a landscape of manufactured artefacts, the Thatosphere is utterly unlike the environment of any other living creature. And although the hand has played an important part in our ascent to the Thatosphere (see my The Hand: A Philosophical Inquiry into Human Being, 2003), it is language, above all, which has expanded our capacity to make explicit what, who, and where we are.

However, highlighting what-is as ‘that which is the case’ is shadowed by a sense of things – objects, states of affairs, events – that only might be the case. We have a vastly extended, articulated, and structured sense of possibility, immeasurably different even from that of our nearest primate kin. So I say: man is the possibility-creating animal.

Possibly So

Possibilities are elusive entities that have many striking features distinguishing them from actualities. The most obvious is that they exist only insofar as they are entertained. Two other characteristics are equally important: they are general and they are located in the future.

First, generality. Possibilities, unlike actualities, do not have absolute individuality. For example, the seemingly specific possibility that Felix the cat is in the garden can be realized in countless different ways. Describing exactly where Felix-in-the-garden is, his posture, the arrangement of the hairs in his fur, and so on, is an incompletable task. Actualities – that which is – will always be more specific than any possibilities in which they are entertained.

As for possibilities being located in an imagined future: this is obviously the case when we anticipate something that might happen but has not yet done so. But futurity is also a characteristic of things that have actually happened but have not yet been experienced – something, for example, that we might seek out or anticipate finding to be the case. Here, what lies in the future is confirmation that what might be the case is in fact the case.

Generality and futurity by contrast are not features of actuality. That which is actual is precisely what it is, period; and it is precisely when it is.

So what? Am I making a three-course meal out of a single pea? No. The ability to entertain irreducibly general, inescapably future, possibilities, is central to the exercise of our freedom: as agents, we act from a realm of what might be, which is general and future-tensed – we act from a virtual outside on the particular, tenseless realm of the actual (see ‘The Mystery of Freedom’, Philosophy Now 140, for more on this).

But possibilities are also interesting for another reason. That which might be seems to lie in an ontological grey zone between that which is and that which is not; between something and nothing. Unlike pure nothing, the possibility that Felix is in the garden is not featureless. It is, for example, different from the possibility that Rover is in the garden, or Felix is in the street. Nevertheless, it may not be realized, and hence fail to be that which is.

It is difficult to get one’s head round this ambivalent nature of possibilities – that they are neither something nor nothing. This difficulty may explain some of the confusion surrounding attempts to make sense of certain paradoxes in quantum physics. But before we enter this baffling territory, let us look a more homely example: the possible results of tossing a coin.

There are, it’s generally assumed, two possible outcomes of a coin toss: heads or tails. If the coin is properly minted and the tossing is not rigged, heads and tails should occur with equal frequency – though, due to chance variations, this may not be evident until there have been a large number of tosses. Indeed, the convergence to 50/50 is seen as a reassurance that the outcome is not rigged through human interference, and this explains why we regard possibilities and their relative frequency as manifestations of the natural world.

Not so fast. When we toss a coin there are not just two but in fact innumerable possible outcomes of – countless possible futures attached to – this action. The classification ‘heads or tails’ overlooks the wide range of actual physical outcomes of tossing the coin. The distance the coin travels; the number of wobbles it has after landing; the number of blades of grass bent as it rolls to quiescence; how far they are bent; how many insects are upset and in what way; and how many grains or even molecules of soil are displaced or disturbed, are just some variables acquiring definite values. And then there are consequences rippling out from the coin’s trajectory. Of course, none of these are relevant to the decision as to who bats first [coin tosses decide that in cricket]; but they are real events in the natural world. The fact that they are for the most part minute does not mean they are unreal. Scales are not part of unobserved nature: atoms are as natural as mountains. Different scales of observation simply reflect our interests and the concerns that invent and apply them, but nature is not a snob differentiating the relevant from the irrelevant, elevating some aspects of events to the status of signals and downgrading others to noise. The actual is no less actual for being irrelevant to us.

I could go on, but my point, I hope, is made. Natural events count as outcomes, that is, as realisations of possibilities, only if they are entertained in the first place as possibilities by conscious beings. The ranges of possible events, such that they have a certain probability of occurring, likewise exist only insofar as they are laid down by our interests or the conventions to which we subscribe. So the belief that there are only two possible outcomes of a coin toss, and that, if the toss is properly conducted, those outcomes have equal probability, does not correspond to an objective truth about the natural world, but to the natural world seen through the lens of interests and conventions that permit us to ignore countless details of the outcome of tossing the coin so that it boils down (or boils up) to ‘heads or tails’.

A Quantum of Ignorance

We can conclude from this that probabilities are no more objective features of the physical world than are possibilities, which of course exist only insofar as they are envisaged. Which brings us to quantum mechanics. The very name of Heisenberg’s famous Uncertainty Principle reminds us that quantum probabilities, like other probabilities, are inseparable from an explicit sense of our ignorance. Probabilities, focussed on a particular area of what might be, are defined by our interests. So probabilities cannot be separated from ignorance, and (conscious) ignorance cannot be separated from possibility, the sense of what might be. Hence the validity of Bruno de Finetti’s assertion in Theory of Probability (2017), that to endow probabilities with an actual objective existence is “analogous to superstitious beliefs… in fairies and witches.”

This reifying of probabilities and locating them in the natural world accounts for much of the seemingly endless debate about what, if anything, quantum mechanics tells us about objective (mind-independent) reality. To think of quantum observation or measurement as bringing about a transition from reality-out-there as a cloud of possibilities or possible values, to an actuality within a given range of values, is to project our ignorance into the natural world and suggest that the world itself is ontologically blurred. In fact, the transition made by measurement is not from the possible (which exists only insofar as it’s entertained by minds) to the actual, but from ignorance to knowledge. Nothing in this transition corresponds to the much-talked-of ‘collapse’ of multiple superimposed states of a quantum system to a single definite state when an observation is made.

There is much more to this story, and it occupies many pages in my most recent book Circling Round Explicitness: The Heart of the Mystery of Human Being (2025). But I want to slip away from the tangled realm of quantum mechanics (which is something of an away match for your columnist) to another realm of science in which possibilities are naturalized: neuroscience. For an increasing number of neuroscientists, our experience of the world is woven out of a sense of what is possible which is continuously corrected by further experience. According to this ‘predictive processing’ theory, the brain is a predictor of sensory input, which is then compared with actual sensory input. For those who embrace this theory, notwithstanding that the brain is a material actuality, it is mysteriously able to generate a future tense to house predictions that can be corrected by other experiences also generated by the brain. In short, the mind is able to entertain possibilities that may or may not be actualized. But this theory has no explanatory power if nothing explains how possibility can awaken in actuality, in the material brain. And so we come back to Man, the Possibility-Bearing Animal. The ability to entertain, articulate, and share possibilities lies at the heart of our distinctive humanity and the greatness (for good or ill) of our achievements. Inquiry, imagination, dreams, hopes, ingenuity, are all founded in our ability to reach beyond what is delivered to our senses – what is actually before us – to what might or might not be, what is unknown, or what is not yet. So while there is some truth in WB Yeats’s assertion (in his poem ‘Under Ben Bulben’) that “measurement began our might”, there is a deeper truth in the notion that our might ultimately lies in our capacity to reach beyond what is to what-might-be. In might began our might.

Raymond Tallis’s Prague 22: A Philosopher Takes a Tram Through a City is out now in conjunction with Philosophy Now.