Perry employed Alice to sell a parcel of real estate at a fixed price without knowledge that David had previously employed Alice to purchase the same property for him. Perry gave Alice no discretion as to price or terms, and Alice entered into a contract of sale with David upon the exact terms authorized by Perry. After accepting a partial payment, Perry discovered that Alice was employed by David and brought an action to rescind. David resisted on the ground that Perry had suffered no damage for the reason that Alice had been given no discretion and the sale was made upon the exact basis authorized by Perry. Discuss whether Perry will prevail.