The healing power of plants and herbs is the subject of the Friar's soliloquy. He does, however, caution that certain herbs used for healing might also be toxic. This, of course, foreshadows the sad events that will take place later in the play. Plants provide nourishment to animals and humans, but they can also be harmful if not used properly. The same can be said of doctors and herbal remedies. Romeo and Juliet are doomed from the beginning because they are two people who were brought up in different ways who therefore have no way of understanding one another. They go out into the world to find love and happiness, but it is impossible for them to do so because they are from two different worlds that would always remain apart. Friar Lawrence's soliloquy reveals that love is the only thing that can bring two people from different backgrounds together. It shows that even though Romeo and Juliet don't know how they will ever find love, the friar believes that they are capable of doing so because love has the power to change everything.