The question failed to provide the blanks spaces but I have come across this, here is the complete sentence with blanks filled;
Mistakes can be mistakes of "Fact", which allow a contract to be voided or mistakes of "Value", which do not.
For a mistake to discredit an
agreement, it typically should be a shared one about a material actuality or
fact. Rarely a one-sided mistake will discredit an
agreement.
