Today's episode features a considerable amount of spontaneous stabbing. We start off with the famous case of Watts v Brains (1600), where the court has to deal with two major problems. First, is it OK to kill someone just because they make "a wry face" at you? Second, how do we prove malice aforethought (and therefore that someone committed murder) if one person kills another in the heat of the moment?

We go on to see how the famous judge, Sir Edward Coke, decides to solve these problems by changing the rules of the game. From now on, he tells us, we can just presume that it's murder when one person kills another without provocation.

This brings us on a whirlwind tour of the idea of provocation. Can you be provoked by verbal insults? Rude gestures? Slaps? The loss of a stranger's liberty? Adultery? What else? The answers may surprise you.

As always, sources and pics on the website: http://www.historyofmurderpodcast.com/ . You can follow the show on Twitter at @Murderhistorian.