Collins v Wilcock [1984] 3 All ER 374 â€" "Generally speaking consent is a defence to battery and most of the physical contacts of ordinary life are not actionable because they are impliedly consented to by all who move in society and so expose themselves to the risk of bodily contact. So nobody can complain of the jostling which is inevitable from his presence in, for example, a supermarket, an underground station or a busy street nor can a person who attends a party complain if his hand is seized in friendship, or even if his back, is (within reason) slapped" (LJ Goff)