“Feelings are like topsoil-great for growing weeds, terrible for holding up a roof. If you don't dig down to something that breaks your shovel, you aren't building a house; you're just camping.”Samuel Walker · Peter James Stouffer
This comes from the fourth epigraph, where Samuel compresses the whole logic of his argument into a construction metaphor plain enough to stand on its own.
He is not arguing that feeling is false. He is arguing that it is insufficient as a foundation. Topsoil can grow things. It cannot hold a structure when weather arrives.
The line matters because Samuel never speaks in abstractions for their own sake. He reaches for houses, shovels, and ground, because those are the materials his moral vocabulary is made from.