What foolish method do the boys use to ensure that they find ralph? what does this decision suggest about the power of hatred and violence versus the power of reason?/?

The answer is: they burn down the bushes and trees

When the boys decided to burn down the area in order to find ralph, they knew really well that their action could potentially resulted in fatalities for ralph.

From this, we can say that the power of hatred and violence often clouded our ability to reason properly. The boys overlooked the fact that burning the bushes and trees could endanger the environment around them and even endanger other people beside ralph.