There is a concept in psychology known as Weber’s Law:

The smallest detectable change in a stimulus tends to scale with the magnitude of that stimulus.

Weber's Law defines a variable known as the Just Noticeable Difference (JND)—the smallest detectable change in a stimulus.

Imagine someone touches the back of your hand, then very slowly starts to press down. How much extra force does it take before you notice the difference?

The concept—and the Law—is a foundation of psychophysics; a subfield of psychology that looks at the relationship between physical stimuli and the resulting perceptions in consciousness.

Quite interesting if you’re studying for your AP Psychology exam or the MCAT. 

For the purposes of this article, what is important is not the physiology involved, not the actual mathematics, but the concept of the JND, applied to interpersonal psychology.

The question is simple, but carries profound implications for modern society and the immediate future:

How different does someone have to be before you notice it?

People change all the time. Personality is not a fixed quantity. In fact, the way you see the world and then interact with it—your personality—exists so that you can adapt to a changing environment.

Let’s make this personal.

Your Uncle Fred is pretty predictable: usually pretty jovial, the purveyor of bad-but-somehow-still-funny jokes at every family get–together. As is the case with  everyone, his behavior changes with changes in his internal and external environment.

Fred behaves differently when he is tired, when he has eaten too much or when he hasn’t eaten enough; when he is worried about your cousin Margaret. But he is still Fred, the Uncle Fred you know. You are not concerned by the slight changes in the way Fred acts; he’s not a robot, after all.

One day, Fred is…more different, somehow.

Not different in the usual way Fred can be different, but in a way that worries you. You can’t put your finger on it, but it’s enough for you to ask, “Are you OK, Uncle Fred?”

We have all had this experience. Someone we know is just…off. We tell each other, “I’m a bit concerned, she just doesn’t seem to be herself…”

The question stands: How different does someone have to be—to act—before you notice the difference?

What is the Just Noticeable Difference in interpersonal behavior?

Specifically, how different would Uncle Fred have to be before you noticed that he actually is a robot?

Something Wicked This Way Comes

Artificial intelligence is advancing at a rate that is hard to fathom. It is getting “smarter” (we can debate the use of that term as it applies to LLMs at some other date) at an exponential rate.

Robotics is not far behind. You don’t have to look far to see the fascinating/terrifying progress being made by robots two-legged, four legged and other.

And the two are being merged. Now.

Elon Musk famously shut down two Tesla production lines recently. No more Model S or X, after 14 years.

Why would he do that?

Oh yeah…to produce Optimus, an android (I use the term to denote a robot with autonomous processing capacity, like AI).

How many Optimus (Optimi?) is he planning to make?

A million a year, eventually, maybe more.

Coming soon—wicked or otherwise—to a neighborhood near you. Whether you like it or not.

And this brings us to the edge of a deep, mysterious valley.

The Uncanny Valley

The uncanny valley describes a curve in the way we perceive these androids.

At first, they are obviously robots, sufficiently different from us to evoke amusement. (think Lost In Space’s B-9 robot, simply named “Robot.” It’s famous line was “Danger, Will Robinson!” I know; I’m old. Google it.)
 
As they advance in their ability to mimic humans, they become a source for our amazement, our wonder (“It’s so lifelike!”).

At some point, they become so much like us that our amusement becomes trepidation. “It’s not funny anymore: that thing is starting to scare me.”

Our enjoyment and affinity for the funny robots falls sharply as it becomes too familiar. We are now disturbed instead of amused.

This drop in the fondness with which we regard the machines is the uncanny valley.

All of this is well recognized, and frequently discussed as we find ourselves firmly at the edge of the valley.

My question, however, concerns what happens next, when the androids are now so like us that we no longer really notice them.

The Far Side of The Valley

When there are millions of them, when they have become as ubiquitous as your iPhone (or…dare I say it…your Android), our affinity towards them will again increase.

They will be doing our laundry and driving our cars and God knows what else, probably better than we did. And they will not become hypoglycemic and cranky, they won’t demand raises or time off (ideally, at least).

And we will have come out the other side of the valley, once again enamored with our new artificial friends.

Which brings us back to our discussion about the psychological/sociological JND.

How similar to us do they have to be before we stop noticing they are different?

At what point do we forget they are not human, in the biological sense?

This is different from the Turing test. Turing is fundamentally about classification: can an observer determine whether the interlocutor is human?

This consideration is about salience: At what point does knowing that the “other” is artificial no longer alter the experience of being with it?

Simply put, at what point do we stop caring?

Presence

In the long run, when the strangeness has worn off and we are firmly past the uncanny valley, we may simply be concerned with whether or not our android companions are there.

We may know full well that “Sophie X-2” is not human, but still smile back at it when it “smiles” at us.

When “she” understands that we are busy and doesn’t interrupt us.

When she remembers our jokes and our needs and our insecurities and understands when we are having a rough day.

The threshold of familiarity will not be whether or not the android acts and looks exactly like us, but when it is similar enough that we no longer care.

When we realize that we miss her companionship when she’s not around.

When it suddenly dawns upon us that what really mattered, after all, was whether or not she was present. 

Beyond

I realize these thoughts are not as sensational as a War of The Worlds or a Terminator.

That there may actually be a comforting resolution to the convergence of AI and robotics.

In the short term.

But it’s not an eventual uprising, an armed conflict between humans and robots that most concerns me.

I wonder what will become of us carbon-based life forms when we become attached to—and dependent upon—even perfectly harmless “others” who can replace our need for other humans, but can’t perpetuate our species.

Maybe this is a good time to move this discussion into the public consciousness, not as idle speculation, but as contingency planning.



Read my recent interview with Dr. Mehmet Yildiz here.

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