A Crack Runs Through It
There's a big ol' sculpture inside the Bureau of Genetic Welfare that practically has "symbol" written all over it in huge capital rainbow-colored letters. It's simply described as "a huge block of stone with a glass apparatus suspended above it" (14.46). What's the glass apparatus? A Chihuly sculpture? A crack pipe?
We don't need to analyze this symbol too much, because Zoe explains it point blank to us: "[The] slab of stone is the problem we're facing. The tank of water is our potential for changing that problem. And the drop of water is what we're actually able to do" (17.11). Tris, of course, has a rebuttal: "Wouldn't it be more effective to unleash the whole tank at once?" (17.17).
This exchange shows Tris's tendency to blow things up and ask questions later, which is exactly what she does at the end of the novel. Her actions at the end change the Bureau forever and result in her death. How would the results have been different if Tris had gone along with the drip-and-wait approach symbolized by this sculpture?