How slight that bridge commonly is, how much an affair of trestle and wire, we can hardly conceive until we have trained ourselves to an extreme sharpness of introspection.

• 这座桥的可靠性如何，它所依靠的桥墩和结构的强度多大，那只有在我们学会体验极尖锐的自我内省时才能认识。