In yesterday’s post I said, “A 71-year old man like McCain is mentally slower and less flexible than a younger person, and more likely to have his job performance impacted by a major illness.” Many of you objected to my agism.

It appears that there were three reasons for objecting:

1. The commenter interpreted my statement to mean every old person is mentally slower than every young person, which would be stupid.

2. The commenter objects to agism on principle.

3. McCain is obviously healthy and energetic and smart enough for the job.

The first two categories aren’t worth a response. I will address the third point, that McCain is an exception.

First, I will acknowledge the possibility that the smartest and most creative person in the world could be 100 years old. That could happen if, for example, that person started as the smartest person in the world and didn’t decline much. What isn’t likely is that the smartest person in the world started out in the middle of the pack and got smarter after the age of 70.

I will also acknowledge that a mentally active person, such as John McCain, can reduce the normal rate of mental decline associated with age. And with experience he might acquire more relevant knowledge while only forgetting things that aren’t much use on the job, such as his old high school locker combination.

Here’s a link showing that older people can stave off the typical mental decline associated with age by “training” their brains: http://www.washingtonpost.com/wp-dyn/content/article/2006/12/19/AR2006121900901.html

I will also acknowledge that if you were hiring someone to work for your own company, the 71-year old could be the most qualified candidate. But the odds of that happening decrease as the applicant pool increases. The presidency has an unusually large pool of applicants.

And the job at your company is unlikely to be similar in mental requirements to being President of the United States. It’s hard to imagine a job that would require more mental dependability than Commander in Chief.

We have one recent experience with an older president: Reagan. And his mental functioning was clearly impaired by age. While you might argue that Reagan’s results as a president were good, you have to acknowledge the risk involved in having a president who isn’t thinking clearly.

John McCain’s current mental ability does appear up to the task of being president. But like Reagan, he’s at an age where decline can happen quickly. He’s unlikely to be the same man at the end of the first term, much less a potential second term. While it is entirely possible – even probable – he could keep his mind sharp enough to do the job, the odds are unambiguously better for a younger candidate.

President of the United States isn’t the sort of job where “sufficient” is good enough. I have every reason to believe a 71-year old would be sufficient. The odds of being exceptional are much lower.

In other professions, how often do people over the age of 70 produce innovative or exceptional results? Look around your home or office and ask yourself how many of the technical innovations came from senior citizens. How many of the best selling books on your shelf were written by senior citizens who weren’t already famous? How many senior citizens wrote the music you have on your iPod?

You will be tempted to point out exceptions to the rule. Warren Buffet is a good example. But he plans to retire. Alan Greenspan already did. Evidently they think age matters.

If you think age isn’t a factor in the presidency, would you vote for a candidate who was 100-years old and healthy?