once bitten, twice shy

• once burned, twice shy
• once hurt, twice shy

Once bitten, twice shy.

1. One is cautious if he or she has been hurt in the past.

• a burnt child dreads the fire
• the burnt child dreads the fire
• A beaten dog may cower before a friendly hand.
• Bitten by a snake on one morning, afraid of the rope by the well for ten years.

Similar phrases using elliptical causation ("if/then"):

• another day, another dollar
• fall seven times, stand up eight
• finders, keepers
• first come, first served
• in for a penny, in for a pound
• laugh before breakfast, cry before supper
• least said, soonest mended
• mo' money, mo' problems
• no body, no crime
• no cross, no crown
• no fears, no tears
• no guts, no glory
• no harm, no foul
• no hero, no villain
• no losers, no winners
• no pain, no gain
• nothing ventured, nothing gained
• out of sight, out of mind
• waste not, want not

• Gregory Y. Titelman, Random House Dictionary of Popular Proverbs and Sayings, 1996, →ISBN, p. 261.