Water does not boil at 100 °C

Our daily lives rest on numerical values and convictions drawn from experience, treated as universal truths. But what do they represent for us, and for reality?

Opening

There is no doubt that the use of certain linguistic and numerical values has led to astonishing results in our daily lives. Being certain that we can describe a given phenomenon in a shared way comforts us and makes nature less frightening than it might actually be.

We make wide use of these certainties to regulate our relationships with others and our own lives. Being able to reason about a concept using the same shared meanings, as well as numerical elements that define and reinforce its identity, allows us to agree on common events and even to build habits.

A First Point of View

Consider the example of a person who has the habit of having breakfast at a café every day before taking the train to work. Let us suppose that working hours begin at 9:00 and that the train journey takes about an hour. Let us also suppose that the most suitable train for arriving at the office on time is the one at 7:55.

Reasoning backwards, we understand that, if this person wanted to have a good, leisurely breakfast at the café, they would need to get there at least 30 minutes before the train departs. This would leave them time to walk to the station, which is not far from the café. The walk from home to the café takes about five minutes. The alarm should therefore ring around 7:00. The arrangement also works because the café opens at 6:30.

With these times, the person can organize their morning with reasonable certainty of managing to have breakfast and catch the train on time.

The Use of Conventions

All the times given in the example show us how advantageous it is to have a shared system for measuring time. If the community coordinates through a single method of measurement, we can divide the day into specific units of time that hold the same validity for everyone. This is an enormous advantage for society: it allows us to coordinate our activities, set appointments and build shared habits.

That said, I think it appropriate to broaden our view for a moment from the particular to the general, and to ask ourselves what this division of the day and of time into numerical values, which we use constantly, actually is. More generally, to ask what these constructs are that we use to define our existence.

We know that the length of the day refers to a natural phenomenon, namely the rotation of the Earth on its axis. For convenience we have divided the day into 24 hours, even though the sidereal day, that is, the actual time the Earth takes to rotate relative to a fixed point in space (the stars), lasts about 23 hours, 56 minutes and 4 seconds. It is certainly more convenient to organise the day using whole, easily divisible values rather than constantly referring to more complex fractions.

From this observation we can infer at least two things:

• The hour we habitually use to mark our commitments originates from a natural phenomenon to which we have applied a conventional subdivision.

• Clock time, as we use it in daily life, does not perfectly coincide with the natural phenomenon it refers to: humans rely on a natural phenomenon, but adapt it to their own needs.

Going Deeper

Let us return to the initial example. We said that the person determines their movements and activities by using a shared system of time measurement: the hour.

We then made a brief reflection that led us to understand that the hour is not something that concretely exists in nature, but an abstract concept that we use to describe and organize a natural phenomenon. We refer to the rotation of the Earth and divide it according to criteria that are useful to us for organizing our day.

What, in my view, we must bear in mind is that we too often fall into the error of regarding as absolute truths concepts that derive, at least in part, from conventions. These in turn derive from the results of reasoning about natural phenomena.

The path works more or less like this: we start from the observation of a natural phenomenon and study it with the tools at our disposal. Among these, mathematics allows us to describe and quantify more effectively and objectively what we observe. From this study we extract values and build concepts. On these values and concepts we then base a part of our lives.

A spiral is created in which the point of arrival does not coincide exactly with the point of departure: we come close, but something changes; that variation is determined precisely by human reasoning.

If everything starts from a natural phenomenon, our reasoning leads us to extract from reality linguistic and numerical values that we use as a basis for building our lives. But our own life is itself a natural phenomenon!

The constant use of these constructions, together with their effectiveness and usefulness, can gradually lead us to forget their origin. We become convinced that they are realities endowed with an identity of their own, irrefutable because true, and that their truth depends precisely on the incredible effectiveness they show in use.

The more we use them, the more we risk convincing ourselves that they are reality itself, rather than tools through which we try to understand it.

Water Doesn’t Boil at 100 °C

Let us now come to the explanation of the assertion that gives this article its title.

Our starting point is always nature, reality. After all, we can dig logically into a natural event to try to understand its origin or workings, but our analyses always begin from a comparison with something that manifests itself in the real. So, we observe the real.

In observing the real, we come to formulate hypotheses and theories. If verified, abstractions can follow from them, such as the hour, which can prove useful to us.

But how does nature itself act?

Take water, for example. Water does not possess a consciousness like ours, nor scientific knowledge that allows it to know that, upon reaching a certain temperature, under particular conditions of pressure and composition, it must boil at exactly 100 °C.

Water, more simply, changes state when certain physical conditions are met. It does not “wait” to reach 100 °C: its behavior depends on the conditions it finds itself in.

The phenomenon, the change of state, is determined by the physical conditions of nature.

A distinction emerges that will be fundamental for what follows: the phenomenon does not coincide with the concept through which we describe it. Water changes state regardless of whether we have devised a scale for measuring temperature. The phenomenon belongs to reality; “100 °C” belongs instead to our way of describing it.

This does not mean that the temperature value is false or useless. On the contrary, it is an extremely effective tool for describing a certain behavior of water under certain conditions. The point is another: we must not confuse the tool with what the tool describes.

Back to Ourselves

Let us now think of the person in the example and imagine them as a little droplet of water. This is an image often used to remind us how small we are compared to the immensity of the reality around us. I would not abandon that meaning, but in this case the focus is on the difference between the person understood as an element above or detached from nature (as they are used to thinking of themselves) and the person as immersed in the nature of which they are a part, as they actually are, exactly like the droplet of water.

We too are a natural phenomenon. A complex one, given this incredible consciousness of which we still know very little. In any case, we are the result of a natural process. We are immersed in nature and are part of it.

If we compare ourselves with the behavior of water, here is what we can notice: water simply acts, following natural conditions. Humans, starting from natural conditions, create constructs on which they base their actions. It is the natural use of reason that leads us to do this, but inexorably, we detach ourselves from nature.

The use of the hour, as we understand it, is certainly useful in a society that has to coordinate its activities. My point is therefore not a criticism of the international systems used as conventions to regulate our activities, but of the idea that we may end up attributing the value of absolute truth to constructions we have devised to describe nature.

Extracting concepts from nature through reasoning and using them to organize our lives is one of the greatest capacities of the human being. The risk arises when we forget that those concepts are tools we have built to understand something that exists independently of us.

Conclusion

It is therefore the natural phenomenon, to which we refer in our scientific and philosophical reasoning, that constitutes the starting point of the linguistic and mathematical conventions we use to organise our daily lives.

We must, however, always keep in mind that everything we have been able to build derives, directly or indirectly, from our relationship with reality. It is to nature that we must continue to look, and from it we can draw inspiration, without confusing our constructions with what they seek to describe.

Looking at the finger instead of the moon, in the end, means precisely this: focusing on the tool and forgetting what the tool is supposed to point us toward.

The intention is not to argue for abandoning the conventions we have created. They are extremely useful in everyday life and indispensable for the functioning of the community. But we cannot attribute to them the value of truth by virtue of the fact that they demonstrate great practical effectiveness for human beings.

They are human constructs that do not exist in nature in the form in which we conceive them, but which originate from nature and which we use to organize it conceptually.

Let us therefore look at the reality around us with a more open eye. Let us not allow ourselves to be limited by conventions, however useful they may be.

This is perhaps the initial state of any form of reasoning: listening to reality and, when necessary, calling into question theories of which we were fully convinced, remembering that, after all, they are constructs deriving from our reasoning about reality, but are not reality itself; and therefore, for this very reason, probably always open to doubt.

Truth is in nature. Science and philosophy are the tools we have at our disposal to try to understand it; but what we build through them is not reality itself, but a representation, a model, a concept that helps us understand it.

Nature does not do calculations the way we do. Nature simply is.

Just as water does not “boil at 100 °C” in an absolute sense: it changes state when the physical conditions surrounding it make it possible.