Perhaps the most famous example of Game Theory in action is in 'The Prisoners' Dilemma'. Here 2 suspects have been caught by the police, but the police only have enough evidence to charge them with trespassing but they are sure the prisoners have stolen something. They decide to offer them a deal to get them to 'rat' on each other. The police would like to get both the prisoners for theft - so they set up the deal in such a way that it is preferable for both the prisoners to rat on each other. Please consider the following table:
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Therefore 'ratting' is the dominant strategy, but does not wield the optimum result for the group - which would be if they both cooperated and each only got 4 years instead of 10 years each when they both rat.
Now from one quite complicated and serious situation to a little more fun one: you are one of three cowboys having a 'Truel', and you're turn is first to shoot - for simplicity's sake let's presume that none of you ever miss. Who should you shoot? Strangely it would be best for you to purposely miss because if you kill one of them then the other would kill you in his turn. Even more bizarrely, by everyone adopting this 'dominant strategy' then no one will ever shoot anyone else - yielding the best outcome for the group, where everyone stays alive. So in this situation the theory of Adam Smith is correct. but unfortunately this isn't always true.
I hope to by now have convinced you that mathematics, or at least parts of it, can be interesting. If I have managed to wet your appetite for more then I recommend you watch 'A Beautiful Mind' and have a read of 'Rock, Paper, Scissors' by Len Fisher.
Also please bear in mind that I am not a mathematician and only understand this whole thing to a very basic level, so if you have any complicated questions I'll try my best to answer, but can not promise that I will be able to.