Simplify the following text for a Grade 9 native English-speaking person.
Original: Locke coordinated the advice of several physicians and was probably instrumental in persuading Shaftesbury to undergo an operation ( then life-threatening itself ) to remove the cyst . Shaftesbury survived and prospered , crediting Locke with saving his life .
Simplified: Locke used the advice of several physicians and persuaded Shaftesbury to go to an operation .