Kingís Bench, 1466.
Y.B. 5 Edw. IV, folio 7, placitum 18.
Prosser, p. 4
I donít know if this is a case, but the idea is that the guy who would become the famous Chief Justice Brian says that itís always your duty to do anything you do in such a way that you donít harm others. Even if you didnít mean to harm somebody, if they get hurt, they can sue you. Even if youíre doing something lawful, like defending yourself, if you hurt somebody by accident and without intent, the person could still sue.