A Nobel Laureate in Physics once argued that scientists did their best work prior to the age of 40. Food for thought on the subject comes from a researcher at Northwestern University's Kellogg School of Management who has analyzed the relationship between age and innovation. There's plenty of anecdotal evidence that creative output peaks around the early 30s or late 20s, then gradually declines. Einstein, for example, published his Special Theory of Relativity when he was just 26.

This pattern of declining creativity apparently holds for such endeavors as lyric poetry, pure math, and theoretical physics.

Interestingly, it seems that the average age at which great achievements are attained has steadily risen, trending up by about eight years over the course of the last century. The big question is, how come?

One factor pushing up the average age of great innovators is that Ph.D.'s now finish their academic work substantially later in life than they did a century ago. This seems to explain four years of the eight-year delay in peak performance.

The thought is that it takes longer to earn a Ph.D. simply because there is more to learn. When there is a lot of fundamental knowledge to master in a given field, practitioners will probably decide to get more education rather than less. And more education tends to make people better innovators. But education comes at a price. You can't innovate when you are studying. And by studying longer, warns the NU researcher, there is a real danger that creative people are reducing the quality of output they can expect to achieve over their careers.

Personally, I think other factors besides the length of the education process are delaying the point at which innovators hit their stride. Educators are good at recognizing great students. But great innovators tend to be unconventional thinkers, and the evidence is that most educators are terrible at recognizing that trait among students. They may even mistake it for stupidity. Truly creative professionals may have to overcome the baggage of what may well be a lackluster academic career before their ideas are treated seriously. This takes time.

Certainly the best engineers I've known fit this pattern. None of them were much better than C students. And the most outstanding engineer I've ever had the honor of working with got a D in his senior design course. Here's how it happened:

It was back in the days when digital desk clocks had just come out. My friend Jeff decided to design one. This was, of course, long before the circuitry for such appliances had been shrunk onto a single IC, or even onto a chip set. To build his clock, Jeff had to dumpster dive at local factories and fish out defective static-RAM chips. He wrung out the chips with an oscilloscope and figured how to bypass the bad memory bits. Leads on the chips typically were clipped off, so he had to carefully solder straight pins onto the DIPs to make connections. He went so far as to learn how to fabricate his own printed-circuit board. The case for the clock was a cardboard laundry-detergent box that Jeff had painted and lacquered until it looked professionally done.

In fact, the whole project looked like a professional job. And that was the problem. The instructor was convinced that Jeff had just bought a kit and assembled it. Nothing Jeff said or did could change his mind.

Innovation is a key to economic growth and development. But if innovators are getting a late start, it is more likely due to what schools are teaching rather than how long it takes them to teach it.