Investors should be skeptical of history-based models. Constructed by a nerdy-sounding priesthood using esoteric terms such as beta, gamma, sigma and the like, these models tend to look impressive. Too often, though, investors forget to examine the assumptions behind the models. Beware of geeks bearing formulas.
Warren BuffettSomeone's sitting in the shade today because someone planted a tree a long time ago. The person sitting in the shade now should be grateful for the person who planted and tended that tree. That includes all those benefactors of humanity throughout history that created, invented, financed, produced, maintained and improved all that we enjoy today.
Warren Buffett