Grantham thinks that investors and everyone needs to sit up and take notice of the changes that are happening around the globe. Grantham sees a future of much slower economic growth. It isn't that he is pessimistic, it is simple math. Population growth is slowing and the number of people in the work force is growing more slowly.
Grantham thinks a world of 1.5% growth is what lies ahead which is much lower than the 3% that is general consensus.
Grantham also thinks that there has been a paradigm shift in resource prices. His example is how 50 years ago Saudi Arabia could spend $10 per barrel to get oil out of the ground, while five years from now we will be getting exactly the same barrel of oil from offshore Brazil where we have to go beyond the range of helicopters and then drill beneath the salt dome thousands of feet under the sea.
Here is the link to the half hour audio interview with Grantham: