The world runs on three factors – demographics, technology and upheaval (into which we can dump war, revolution and plague). A fourth might be the feedback among those three; how, for instance, demographics feeds upheaval (nations with lots of young men go to war) or technology causes any amount of disruption (think of the effect of railways on the westward expansion of the US).
Try as we might, we won’t get far from these; at least, not if we take the long-term view where a decade is reduced to a snapshot. That’s the perspective we want if we’re examining a lifetime’s investing. This would span 30 to 40 years. Few will have the resources for serious investing much before the age of 30. Equally few are likely to continue much beyond 70, when earning and saving must give way to spending.
