Of Brown Bowls, Blue Cars and Felt Facts

There are things we think we know.

A rooster, for example.

I have known chickens for as long as I can remember. Hinkel, as we call them here in Hesse, were simply part of everyday life in my childhood home. They wandered around, pecked, clucked and laid eggs. Roosters crowed. Everybody knows that. You don’t need a documentary to tell you.

Or so I thought.

Then I watched a documentary about roosters and learned things about these animals that I had never known. Among other things, it dealt with their perception, their colour vision and, eventually, tetrachromacy.

A new word.

Tetrachromacy.

You have to say it slowly a few times. Then it stops biting.

Humans normally have three different types of cone cells involved in colour vision. Put very simply, we speak of red, green and blue, although the actual processing is considerably more complicated. The interplay between these receptors and the way the brain processes their signals creates the world of colour that seems so self-evident to us that we rarely give it a second thought.

Other living creatures have different possibilities of colour perception. And even in humans, certain genetic conditions can result in a fourth functionally distinct type of cone. The important thing is not merely whether this additional receptor exists. The brain also has to be able to do something with the additional information.

And suddenly I found myself looking at a rooster, an animal I had thought I knew all my life, and had to admit:

I had no idea what its world looked like.

That alone would have been remarkable enough.

And precisely while I was marvelling at how little I knew about the perceptual world of such a familiar animal, a considerably less pleasant thought intruded.

How readily we sort living creatures like these into categories such as livestock, production factor, useful or useless. For male chicks, falling into the wrong category could for a long time mean simply this: does not fit the system of economic exploitation.

A fascinating living creature with a perceptual world we can barely imagine.

From an economic point of view, possibly still a problem.

The rooster has not changed.

Only the category into which we put it.

Categories are extraordinarily useful. Without them, we would probably struggle to get through an average morning. They become problematic when we forget that we were the ones who labelled the drawers.

Colour alone makes that obvious.

How does someone explain a colour to me that I cannot see?

Strictly speaking, they cannot.

You can explain to someone blind from birth that red is associated with certain wavelengths of visible light. You can talk about fire, warmth, blood and warning signs. You can describe receptors, nerve signals and brain activity.

But you still haven’t explained red.

Because red is not a wavelength.

The wavelength can be measured. The red that I see only emerges from what my perceptual system does with that information.

If there is a blue car parked outside my house, I still say:

“The car is blue.”

Of course, I could be more precise:

“Under the present lighting conditions, the light reflected by this object produces an impression in my visual system that I have learned to call blue.”

“Where did you park?”

“Next to the object whose reflected electromagnetic spectrum produces in my visual system …”

By then, the car has probably been towed away.

So we agree:

The car is blue.

It works remarkably well. We have learned labels, and those labels allow us to move together through a colourful world without holding an epistemological seminar at every traffic sign.

Until someone calls the anthracite-coloured bowl “brown”.

My partner once asked me to fetch the brown bowl from the kitchen.

I looked.

And looked.

There was no brown bowl to be found.

Eventually she came into the kitchen herself and pointed at the bowl she had meant all along.

To me, it was dark grey to anthracite.

Now, we could argue about who is right. We could fetch colour charts, examine the lighting conditions and then embark on a relationship conflict lasting several years over a kitchen bowl.

Or we could ask the more interesting question:

What if we really do not perceive exactly the same thing?

We cannot look inside another person’s perception. We can measure, compare and ask people which colours look identical or different to them. But I cannot determine whether my internal experience of blue feels exactly like somebody else’s.

Most of the time, that does not matter at all.

We both point at the sky and say “blue”.

Case closed.

Until the brown bowl appears.

Then it suddenly becomes apparent how readily we equate our perception with reality itself.

And we do not even perceive everything that physically exists.

Our eyes respond to only a small part of the electromagnetic spectrum. Our ears likewise cover only a limited range of frequencies.

Ultrasound does not disappear from the world simply because I cannot hear it.

A dog can react to sounds of which I am completely unaware.

For me, it is silent.

Apparently not for the dog.

So who hears reality correctly?

Neither of us hears “reality”. We simply have different forms of access to it.

Technology can bypass some of our biological limitations. A thermal camera measures radiation invisible to our eyes and translates its measurements into colours we can see.

That does not suddenly make infrared red.

We have merely translated something invisible into the language of our perception.

A friend has spent years working with a similar form of false-colour representation. Among other things, he processed aerial images so that certain differences, barely distinguishable to the human eye, became clearly visible.

The interesting part came afterwards.

He took the images and went outside.

What was actually present at the marked locations?

Were there similarities?

Had the representation made something visible that was worth examining more closely?

The computer had not discovered some mysterious additional colour. It could distinguish between measurements. Those differences could then be displayed in a way that allowed our eyes to make sense of them.

First measure.

Then make visible.

Then go outside and check.

A remarkably sensible sequence.

Especially compared with the equally popular method:

First be convinced.

Then look for evidence.

The limits of our perception are not the limits of reality.

Unfortunately, it works the other way round as well.

We can perceive something that, in the form in which we experience it, is not actually there.

Anyone who has lain awake as a child in a dimly lit room may remember the strange transformation of familiar objects. The same jackets and clothes that hang from a coat stand in broad daylight are still hanging there. But a few shadows, unfamiliar outlines and the right amount of childhood imagination are enough for something threatening to grow out of that familiar object.

A monster.

The coat stand is there.

The clothes are there.

The monster is not.

At night, the child’s brain is not terribly interested in this epistemological subtlety.

Whatever is looming there in the half-light looks dangerous. And a monster is something you can be afraid of.

A coat stand has considerably less talent for that.

At dusk, a tree stump becomes an animal. In fog, something appears to move.

There is an external stimulus. It is simply ambiguous, and our brain turns it into whatever seems plausible on the basis of experience, expectation and circumstance.

Perception is not a camera.

Our brain does not politely wait for every last piece of information to arrive before producing an impartial set of minutes.

It fills in the gaps.

It sorts.

It interprets.

And it expects.

Sometimes, as a result, we even notice something that is not happening.

When I recently came home, I noticed the quiet.

Over the previous days, someone in the house had repeatedly demanded my attention through noise and restless behaviour.

Now he was asleep.

What was remarkable was not a new sound.

It was the absence of the old one.

The expected noise was not there.

Even absence can become information when we were expecting something else.

Our mental state does not arbitrarily alter the outside world. But it does influence what we pay attention to and how we interpret ambiguity.

Someone walking through a dark forest in fear hears an unfamiliar sound differently from someone strolling along the same path, relaxed, in broad daylight.

The forest does not have to change.

The observer is quite enough.

And even the observer does not always remain the same.

Tiredness, fear, attention or psychoactive substances can alter what comes to the foreground, what recedes and what significance we give to a stimulus.

More intense does not automatically mean more true.

Sometimes the explanation for differing perceptions is considerably more mundane.

My children liked mushrooms.

At least, that was what I thought.

Purée them and they were eaten enthusiastically. Put pieces of mushroom in a sauce, however, and the verdict was:

“Yuck!”

I was confused.

Either you like mushrooms or you don’t.

Or so I thought.

Until we talked about it.

The taste was not the problem at all.

It was the texture.

When puréed, the mushroom flavour remained. What disappeared was the sensation of having a piece of mushroom in the mouth, which they found unpleasant.

My question had been too crude.

“Do you like mushrooms?”

I had bundled taste, smell, temperature, texture and mouthfeel into a single judgement.

Yummy.

Yuck.

Case closed.

Only by looking more closely – or, in this case, by asking – did it become apparent what had actually been going on.

Which brings us to a concept that now appears so reliably in the company of meditation apps, incense sticks and cups of tea that it is easy to forget how seriously it is taken in therapy:

Mindfulness.

It does not mean reverently watching a raisin exist.

Among other things, it means consciously noticing inner and outer experiences without immediately judging them and automatically reacting to that judgement.

A sound is, first of all, a sound.

A bodily sensation is, first of all, a bodily sensation.

A thought is, first of all, a thought.

A feeling is, first of all, a feeling.

That sounds trivial.

It isn’t.

Perception, memory, expectation, interpretation and judgement lie so close together in everyday life that we often fail to notice when we have moved from one to the next.

Mindfulness will not make ultrasound audible or give us a fourth type of cone.

But it can help us notice more precisely, within the limits of our perception, what is actually happening – and what we have already made of it.

Things become particularly entertaining when two people remember the same event.

“But I told you …”

A sentence that now makes me put on my metaphorical helmet as a precaution.

Because what follows may be a perfectly accurate memory.

Or something someone intended to say.

Or something that really was said while I was out of earshot.

Or something I simply could not hear.

Or something that was said, reached me, and that I later forgot.

All of these are possible.

Memory is not a video archive.

And even if the sentence was indeed spoken and received, its journey is far from over.

Communication theories like to distinguish between factual content, self-revelation, relationship and appeal. That is already quite a job description for a single sentence.

But before any of that can happen, what is said has to clear another hurdle:

One person first has to translate their perception into language.

The other then has to translate that language back through their own perception, experience and concepts.

So communication can already fail at “Please fetch me the brown bowl.”

And that is before factual content, relationship and appeal even get the chance to start fighting among themselves.

“But I told you to …” is even more fun.

The sentence may contain a claim about the past.

At the same time, it may also say:

You should have done that long ago.

And because you haven’t, you have done something wrong.

Suddenly two people appear to be arguing about whether a particular sentence was spoken yesterday, while the real argument has long since moved on to expectations, responsibility and guilt.

Sometimes it is difficult enough to explain to another person what we ourselves have perceived.

Back in 2001, I once put it roughly like this:

It is difficult to explain colours to a blind person. It becomes impossible when they believe they know better than everyone else.

The truth is:

I do not know whether someone before me had already arrived at the same or a very similar thought.

Damn.

Now I’ve said it myself.

I know that I came up with that wording at the time. I do not know whether that made it new.

Those are two different statements.

And that small distinction takes us straight to the heart of the problem.

What do I know?

What do I believe?

What do I remember?

What can I verify?

And which of those do I subsequently declare to be the truth?

Some time ago, I listened to a speech in the German Bundestag.

Who was speaking and what the occasion was are irrelevant to this particular thought.

Three words stuck with me:

“The truth is …”

Again and again.

At some point, I paid less attention to what followed those three words than to the words themselves.

Why does someone need to announce explicitly that what follows is the truth?

If it is raining outside, I can say:

“It is raining.”

The statement can be checked.

If instead I say:

“The truth is: it is raining,”

I have not made the rain any wetter.

I have merely assigned a special status to my statement.

I am no longer merely making a claim.

I am supplying the instructions for use at the same time:

This is true.

No objections.

That does not make the sentence one millimetre more true.

There are facts.

If a thermometer measures 24 degrees Celsius under defined conditions, that measurement can be checked.

Then there are perceptions.

Those 24 degrees may feel extremely warm to me.

Then there are judgements.

I may find them pleasant or unbearable.

And then there are interpretations.

I can draw conclusions from measurements whose meaning may very well be open to debate.

These levels are not the same.

The expression “feels-like temperature” illustrates this rather nicely.

The weather app obviously does not know how I feel. It calculates additional factors that affect how warmth is experienced by the human body.

I can still sweat.

My body hasn’t installed the app.

With “felt truth”, things become more difficult.

I can feel unsafe.

That feeling is real.

It does not automatically follow that a measurable danger has increased.

I can be completely sincere in my conviction that something is happening.

My conviction is real too.

The event does not therefore have to be.

Things become particularly awkward when scientific findings are suddenly reduced to “opinions”.

Science is not infallible.

That would be a rather peculiar kind of science.

Its very nature is to make claims testable, discover errors, revise conclusions in the light of better evidence and tolerate uncertainty where certainty is not possible.

It does not follow that a well-supported scientific finding and an unsupported counterclaim are simply two equally valid opinions.

“The bowl looks brown to me” can be a completely honest statement about a perception.

Measurable properties of the bowl are a different kind of statement.

Trouble begins when those categories are swapped.

It becomes more interesting still when someone making a false factual claim is not deliberately using it as a tool but genuinely believes it.

Then it is not necessarily a lie.

A lie requires someone at least to believe that what they are saying is untrue.

But what happens when our own conviction eventually becomes the test by which we judge the outside world?

Then the question is no longer:

Does my view match the facts?

Instead:

Do the facts match my view?

And if they don’t, the facts will simply have to go.

That sounds drastic.

The mechanism itself, however, is hardly foreign to us.

We pay more attention to information that fits our expectations. We remember selectively. We interpret ambiguous information through what we already know – or believe we know.

Which is precisely why measurements, verifiable sources, science and other people’s objections can be so irritating.

They may have the extraordinary impertinence to contradict our beautiful model of the world.

Not because those methods are infallible.

But because we certainly aren’t.

While driving one day, I noticed a traffic sign I had passed several times before.

It showed a wrecked car.

Beside it were the words:

“Don’t text and drive.”

The sign was not new.

I just happened to be thinking about perception.

Suddenly I saw not only the warning but found myself wondering why a traffic sign in Germany was using an English sentence.

A German-speaking driver has to process it linguistically and may have to translate it internally. For other road users, English may in turn be easier to understand than German.

The image of the wrecked car hardly needs translation.

The sentence does.

I had passed that sign several times.

That day, I noticed it.

Or, more precisely:

I noticed something about it that I had not noticed before.

The sign was the same.

The observer wasn’t.

And that brings me back to the rooster.

To an animal I had thought I knew all my life, yet which still had things to reveal that I had never even known existed.

We live in a world larger than what our senses can perceive.

Of what reaches our senses, by no means all of it reaches our attention.

What does arrive is sorted, completed and interpreted.

We give it names.

We remember it.

We judge it.

And from all of that, we construct a model of what the world is like.

That is not a flaw.

Without such models, we would probably struggle to get through the morning.

The problem begins when we forget that they are models.

“The truth is …”

Given everything I have perceived, understood, checked, remembered and possibly misunderstood, I currently arrive at the conclusion that …

Would probably be more honest.

A little cumbersome for speeches in parliament, admittedly.

But perhaps not such a bad idea for living together.

Or for the brown bowl.

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