G.K. Chesterton on fantasy writer and fairy-tale teller George MacDonald:

Dr. Macdonald, I fancy, has always known that melancholy is a frivolous thing compared with the seriousness of joy. Melancholy is negative and has to do with trivialities like death: joy is positive and has to answer for the renewal and perpetuation of being. Melancholy is irresponsible; it could watch the universe fall to pieces: joy is responsible and upholds the universe in the void of space. This conception of the vigilance of the universal Power fills all Dr. Macdonald’s novels with the unfathomable gravity of complete happiness, the gravity of a child at play (Quoted by Daniel Gabelman in George MacDonald: Divine Carelessness and Fairytale Levity).