The narrator suggests that often the greatest ideas are what lord of the flies?

On page 143 the narrator states "The greatest ideas are the simplest". This is in response to Ralph deciding to move the location of the fire from the mountain to the beach. The boys ask what they will do now and Ralph says "We'll build a fire". All the boys love this idea and for this first time, Piggy actually helps collect some wood. He never helped earlier because of his Asthma. This is also because Jack has now left the other boys.