Economics is a term for a variety of disciplines which are now so specialised that they could be separate subjects. At its core, it describes the systems and methods by which people choose to allocate resources, and the signals and incentives that they get to do so. Economics would not therefore exist in the same way if we lived in a world of absolute abundance where every need and want was met and there was no cost to doing anything. It fails when there are abundant goods whose use does not stop anyone else using them. That is why it describes such goods as ‘non-economic.’ Instead, economics begins from the idea of choices based on opportunity cost. An opportunity cost is the cost of what was not done, of the ‘next best alternative’ to quote the textbooks. For example, if you had a choice of using your money and time for a birthday meal, or a walk, and you chose the walk, the meal would be the ‘alternative foregone.’ It would be the opportunity cost. This is quite a narrow bas