One day the famed German chemist Justus von Liebig was approached by an assistant, who excitedly declared that he had just discovered a universal solvent. "And what is a universal solvent?" Liebig asked. "One that dissolves all substances," the assistant explained. "And where," Liebig replied, "are you planning to keep this solvent?"

[The hypothetical universal solvent once sought by alchemists? Alkahest.]