The Idea In 60 Seconds

  • In a sense, we know intuitively that people get smarter as they age.
  • The textbooks might tell you different.
  • IQ, what most of us call intelligence, peaks in your mid 20s.
  • Fortunately there is another type of intelligence, crystallized Intelligence which can more than offset declines in IQ.
  • And since the brain is a network, Metcalfe’s Law (explained below) has a significant influence.
  • Unless someone becomes ill, fluid intelligence declines in a linear way but Crystallized Intelligence increases exponentially.

Do We Get Less Intelligent As We Age?

We often focus on the idea of cognitive decline as people age.

After all, any billion dollar tech startup you’ve ever heard of was started by a smart young bloke. Youth is associated with innovation, adaptability, and problem-solving. These attributes relate to what psychologists call “Fluid Intelligence“, essentially IQ, what most of us think of as intelligence.

Fluid intelligence declines over time, after your mid 20s in a pretty much linear way until you die. Of course, some people get Alzheimer’s or one of the forms of dementia and their cognitive decline accelerates precipitously.

Fluid vs. Crystallized Intelligence

Luckily, there’s another form of intelligence that grows as we get older : “crystallized Intelligence”. Crystallized Intelligence, relates to the knowledge, and experience you accumulate over the years. It includes verbal reasoning, general knowledge and reasoning based on lessons learned.

This form of intelligence can continue growing as we age, making older individuals more adept at tasks that require judgment, perspective, and deep understanding.

The question then is, what happens to intelligence overall? To figure this out, we need to consider the mechanism behind the way in which crystallized intelligence improves.

Metcalfe’s Law

Metcalfe’s Law explains the value of networks. It says that the value of a network increases with the square of the number of nodes in the network.

Put simply, if you’re the only person on Facebook, or WhatsApp or the mobile phone network, there’s not much value in you being there. If everyone else is there, there’s a lot of value in you signing up.

Metcalfe’s Law can be applied to human intelligence, especially its Crystallized aspect.

As we age, our brains accumulate more and more “nodes”. Every fact, story, lesson, formula, concept, idea, word experiences, skills, and insights is a new node in your brain.

Over time, with each new piece of information we acquire, the potential number of connections between these nodes grows exponentially, in a way, following Metcalfe’s law. The more “nodes” (or experiences or ideas) we accumulate, the more complex and valuable our network of ideas becomes.

While fluid intelligence might decline, the mind’s ability to draw on the ideas we’ve learned increases.

In effect, our thinking may slow down, but it deepens and becomes more layered, which is an advantage in complex, real-world situations.

Age as an Asset

You can see it in real life. Older professionals, for instance, often outperform younger colleagues in strategic decision-making. Experience allows them to see the bigger picture, connect the dots between elements, and apply lessons learned from previous challenges.

Similarly, in creative industries, we often observe that people’s most profound work comes later in life. Their accumulated experience, mixed with the perspective gained over time, enables them to create art, literature, or ideas that are rich in meaning and deeply informed by lived experience.

As we age, we build a cognitive framework that lets us understand the world in richer and more sophisticated ways, even if we can’t think as quickly on our feet as we did in our twenties.

A New Perspective on Aging

Obviously it’s not exactly the same as Metcalfe’s law – but the research says there are some similar effects as you age. And whether crystalised intelligence more than offsets the decline in fluid intelligence depends on whether you’re prepared to pay attention and keep your mind active. It all shows the value of becoming a life long learner.

In a sense, I think we all know this to be true. Imagine a family BBQ with some men and women in their 50s, laughing with each other and a 25 year old, let’s say young man, trying to join in. According to psychology, the young man is the smart one. His fluid Intelligence (IQ) is at its peak.

It’s hard for me to imagine a real world scenario, though, in which the old people would not substantially outdo the young man. Their experience, the lessons they learned (the hard way) and knowledge of how the world actually works, seem to me to make an obvious and striking difference.

Younger minds may excel at adapting to new problems, older individuals have an intellectual depth that younger people can’t yet access. Of course, if they’re smart, they can draw on a vast network of knowledge to solve problems more thoroughly, if not more quickly.

AI Considerations & How Young People Get The Best Of Both Worlds

Since I work in the field, many of my blog posts contain some mention of Artificial Intelligence and its particularly relevant, here.

The key point is that Large Language Models (LLMs) lack fluid intelligence, or ‘IQ,’ but possess significant crystallized intelligence. In many ways, LLMs are depositories of much of the crystalline intelligence that’s ever been written down.  

Fluid intelligence—characterized by quick thinking and adaptability—typically peaks in your  early 20s. So, that’s a unique advantage for young people that old people (like me) can’t match. Now, young people can combined their IQ with LLMs and all that crystalline intelligence, for free.

In addition to their natural cognitive abilities, young individuals now have access to expert-level knowledge and contextual understanding that typically take a lifetime to acquire.

One of my favorite aspects of Generative AI is the contribution they can make to education around the world. Personal tutors like Khanmigo are a service every kid in the world deserves.

Even in rich countries, young people can also utilize LLMs as on-demand tutors, enabling rapid acquisition of new skills and knowledge.

Younger generations, more inclined to adopt new technologies, often explore innovative uses for LLMs that established (older) professionals might overlook.

And, as we saw in this article, they stand to benefit later in life from the compounding effects of networks, as described by Metcalfe’s Law.

Altogether, LLMs offer young people an optimal blend of youthful IQ and accumulated wisdom, effectively granting them the best of both worlds.