To the novice student, demand and supply analysis looks like a very simple, sensible and powerful way of analysing market behaviour. The examples of demand curves in introductory courses are usually fairly folksy and bland. They’ll be in terms of the kinds of thing we all buy from day to day – chocolate bars or gas (petrol), computer games or shirts. It looks so simple. You can easily imagine your own demand schedule for say, chocolate bars. Then - apparently - you simply add your own demand schedule to all the other demand schedules to come up with a market demand curve. A similar process applies to supply. Then it’s just a case of finding the intersection of the supply curve and demand curve This is the market equilibrium price. If price deviates from this equilibrium, there is a natural mechanism to push the market back toward the point of intersection in terms of excess supply and excess demand. Once you have internalised that model, that’s it – you’re an economist.

Read John-Paul Marney’s essay - Is Economics Unscientific?