how does the absence of " Imagination,Fancy, and Invention" contribute to the kind of people the Laputians are?

The fact that the Laputians suffer from the absence of "Imagination, Fancy, and Invention," leaves them unable to focus on anything outside of intense speculations. They even hire flappers (servants) to watch for danger and lead them around as they're so absorbed with deep thought they might do themselves harm.

"This flapper is likewise employed diligently to attend his master in his walks, and upon occasion to give him a soft flap on his eyes; because he is always so wrapped up in cogitation, that he is in manifest danger of falling down every precipice, and bouncing his head against every post; and in the streets, of justling others, or being justled himself into the kennel."