Fire is a two-pronged symbol. On the one hand, fire relates to Thomasina’s discoveries about the second law of thermodynamics. She identifies that heat tends to leave a system, and won’t re-enter of its own accord. Heat, like jam stirred into rice pudding, only heads one direction—towards entropy and disorder. This contradicts Newton, whose physics only showed processes that can go in both directions. But before Thomasina can sort out the full implications of her discovery—is the universe doomed to end in disorder? Can the future be predicted?—she dies in a fire. Like the fire that consumed Alexandria’s library, all of Thomasina’s knowledge disappears, but ultimately, other scholars will rediscover her theories.