While George was visiting his physician Dr. Smith, George mentioned to Dr. Smith that George wished to sell his expensive sailboat. Dr. Smith expressed an interest in buying the boat from George and offered to pay George $6,000 for it. George had intended to advertise the boat for $12,000 in the local newspaper. But George agreed to sell it to Dr. Smith for $6,000 because George was completely dependent on Dr. Smith for medical care and was afraid that Dr. Smith would stop treating him if he did not agree to sell the boat. Two days after the boat had been sold to Dr. Smith, George wished to avoid the contract. Please advise George of his legal rights.