有备无患 [yǒu bèi wú huàn]

better safe than sorry; good watch prevents misfortune; preparedness averts peril; readiness is all; precautions averts perils; be prepared against want; be prepared and you won't be sorry; have a second string to one's bow; have two strings to one's bow; if one is prepared he will be safe; preparedness prevents calamity; prevision prevents calamity; where there is precaution there will be no danger; with all precautions taken one is safe;