What are Spinoza’s arguments for his, albeit limited, defense freedoms of thought and speech? The first argument is that it is strictly impossible to control another’s beliefs completely (20, 250–51). Since right is coextensive with power, lacking the power to control beliefs entails lacking the right to do so. However, since Spinoza admits that beliefs can be influenced in myriad ways, even if not fully controlled, this argument amounts to a rather restricted defense of freedom of conscience.