Buy A Pig in A Poke
Meaning
Buying something sight unseen.
Example:
Have complete knowledge about that computer before you purchase it. You cannot buy a pig in a poke.
Origin
The poke was a small bag and the pig was a small pig. As related in Thomas Tusser’s ‘Five Hundredth Good Pointes of Husbandrie’ (1580), the game was to put a cat in the poke and try to palm it off in the market as a pig, persuading the buyer that it would be best not to open the poke because the pig might get away.
