"Who had deceived thee so often as thyself?"

This quote by Benjamin Franklin questions who is really responsible for deceiving oneself. He suggests that lot of times, individuals are their own worst opponent and they trick themselves by thinking things that are not true or by falling into bad routines or patterns. Basically, he is saying that people are typically the source of their own problems, and they need to acknowledge this in order to start making favorable changes. It's a reminder to be conscious and truthful with oneself, and to take responsibility for one's own actions and thoughts, instead of blaming others or outdoors situations.