What is the test for a purchaser to rescind a purchase?

The law in Canada has been clear, since the case of Redican v. Nesbitt, [1924] S.C.R. 135, that, once a transaction has closed, a purchaser may not rescind unless he/she can establish fraud, an innocent mis representation creating an error in "substan- tialibus", or breach of a warranty which was intended to survive the closing. For this purpose, "fraud" means words or conduct amounting to a representation of fact which was false, known by the vendor to be false, made for the purpose of inducing a pur chaser to buy and which succeeds in induc ing the purchaser to buy. The representation must relate to something which is material or important to the purchaser. It must relate to something which, if the purchaser had been provided with the information, would likely have changed his/her mind about whether to make an offer to buy the house. For the purpose of this case, an error in "substantialibus" involves a finding that the quality of the house which the purchaser bought is significantly different from the quality of the house which the purchaser thought he/she was buying when the offer to purchase was made. In this case, there was no warranty which was intended to survive the closing. The defendant did not plead fraud, but rather, alleged that there was a misrepresentation leading to an error in "substantialibus".