The figurative language used in the excerpt "The greater our knowledge increases, the greater our ignorance unfolds" is the <u>paradox</u>.
The paradox connects in the same situation two opposite things in a construct phrase that together acquires sense: although it seems more logical that when knowledge increases, ignorance reduces or fades away, the meaning of this sentence is that the more we know, the more we discover that yet we have much to learn; Then, the connection of the increasing knowledge with the unfolding ignorance makes sense.