‘If the tram is late, she’ll get a cab’; ‘if I don’t see you tomorrow, we can meet next week’; ‘if we don’t fix our taxation system, our government will go bankrupt’. These are conditionals, specifically indicative conditionals. We use these sentences all the time, in every context, and they are a vital part of our mental and linguistic activities. We couldn’t get by without them. Everyone knows how to use them. And yet, they have proved incredibly resistant to philosophical explanation. There is absolutely no agreed upon theory of them, though there are many theories out there. As philosophy of language has developed, and sheared off into linguistics – particularly linguistic semantics – more sophisticated tools have been developed to explain conditionals, and yet still there’s no agreement. Philosophers don’t even agree on what would make a good theory of conditionals! So conditionals present the perfect philosophical topic: they are really important to our lives, everyone knows how to use them in ordinary life, and yet…we have no theory of them. However, there has been significant philosophical progress in recent decades; perhaps we’re not far off a solution.