Innovation relies on bigger groups, which then allows a smaller portion of the population to do more.
I have heard this before...in what sense would adding population result in more innovation rather than having a more supportive environment for the people we already have (healthcare, education, financing, etc).
While I tend to agree with you, I find the Japanese are incredibly innovative and they are not growing. Maybe I should look at the rate of innovation and see if that has stalled out with population growth?