Many people don’t fully grasp how the stock market works and what its economic function actually is. Behind all the complicated maths and (deliberate and unhelpful) mystique is a very simple economic function. Entrepreneurs need capital to operate their businesses and individuals need outlets for savings. Individuals can give entrepreneurs money in return for a SHARE of the company’s future profits or a STOCK of the company’s capital. An individual can, at any time, sell this right to a share in the company’s future profits to another individual – this market, which can be organised or informal, is known as the share market or stock market. Below is a great cartoon from the 1950s, unearthed by Graeme Acheson, which provides a helpful (if dated) explanation of how the stock market works.
The Berkeley Earth Project , an independent study of global warming, has found that the earth has become a degree warmer over the past half century. However, the statistical uncertainty surrounding pre-1920 estimates makes it very hard to say much about long-term trends - click here for graph . This is one of my concerns with the global warming debate - we simply don't have trustworthy long-run data which looks at temperature changes over the last millennium (or two). My second concern with the global warming debate is that it is very hard to prove any sort of casual link between global warming and human activity. The scientists may be able to show correlation between global warming and our production of carbon dioxides etc., but correlation is not causation. My third concern with the debate is that those who are sceptical or agnostic are stereotyped as flat-earthers or intellectually-challenged crackpots. This only stifles debate and the progress of science itself.