If I might be so bold as to put forth one slight addendum to that analogy: The rule about No Bears in the Maternity Ward only came to be after a number of case

If I might be so bold as to put forth one slight addendum to that analogy: The rule about No Bears in the Maternity Ward only came to be after a number of cases where someone had brought a bear into a maternity ward, following a long history of bear-free maternity wards, in which time the rule had not yet been needed.