Caveat Emptor is the Latin words for “let the buyer beware”
The general rule at the common law is that mere silence does not constitute misrepresentation.
In general, a contracting party is not under any obligation to disclose to the other party material facts that will help him reach a decision about the contract.
Simply put, the onus is on the buyer to do his due diligence, to make all possible investigations and enquires before purchasing the good failing which he cannot vitiate the transaction.
The common way that this information asymmetry between the buyer and seller has been bridged is through the demand for a legally binding warranty such as a guarantee of satisfaction.
But without such a safeguard in place, the common law rule of buyer beware applies.