In Ken Kesey's "Sometimes a Great Notion," the metaphor of mercury illustrates how fear can drive people to unite instinctively. Just as tiny droplets of mercury coalesce into larger masses, individuals may merge into a collective driven by their shared fears and anxieties. This imagery reflects the notion that, in times of distress, people often come together, motivated by a primal response rather than conscious thought.

The passage suggests that there is a transformative power in this unity. As these separate entities join, they evolve into a single, larger form, diminishing individual fears and creating a sense of security. Ultimately, it conveys that by becoming part of something greater, individuals can overcome their fears, transforming them into a cohesive force moving forward, akin to the mass of mercury flowing toward the ocean.