Allan Kardec. The book of spirits (№ 397222)

Question: What is the biggest obstacle to progress?
Answer: Pride and selfishness; I'm talking about moral progress, for intellectual progress occurs constantly. It even seems at first glance that it doubles the activity of these defects by developing ambition and the love of riches, which in turn, motivates activities that enlightens his spirit. So, what happens is that everything is interconnected as the world's moral and physical, and out of evil can come good; but this situation is only temporary; it will change as people begin to understand that beyond the pleasure earthly things there is happiness infinitely greater and infinitely more lasting.