When should you start a company? It's an ongoing debate with two pretty clear sides: the wisdom of age versus the prime of our lives. 

In a recent thread on Quora, the question attracted a lot of attention, thanks to some big names who jumped to respond. 

It all started late in August when an anonymous user asked:

What do people in Silicon Valley plan to do once they hit 35 and are officially over the hill? Since life in Silicon Valley ends at 35 unless you hit it big or move up in management (and simple logic tells you that most won't), I'm curious what people younger than this think they'll be doing at that age.

Since then, the thread has only grown, mainly with comments from programmers over 35 who found success. Among them were Wikipedia's Jimmy Wales, TechCrunch's Michael Arrington, Netflix's Reed Hastings, Craigslist's Craig Newmark, and Zipcar's Robin Chase. 

Those entrepreneurs were 35, 35, 37, 42, and 42, respectively, when they founded those companies, not surprising since the Kaufman Foundation found the "average and median age of U.S.-born tech founders was 39," and "twice as many were older than 50 as were younger than 25."

Meanwhile, 24- to 35-year-olds have only become more risk-averse with time, according to an American Express survey, which found 16 percent started businesses right out of school, a 12 percent drop from 2007. 

Perhaps that's why a suggestion from Wales, now 47, seemed so on point. "A better question might be," he wrote on Quora, "How can we in the tech community make sure that unusual success at a very early age is not mistakenly thought to be the norm?"

After all, age is only a number.