In the following passage, some of the words have been left out. Read the passage carefully and select the correct answer for the given blank out of the four alternatives.
It is a delight _______________ the illuminating thoughts which came to the minds of these men; and, on the other hand, it is amusing to see how ________________ they launched ________________ on boundless seas when they were unprovided with chart and compass. They were _________ brilliant children, who know little of the dangers of the great world, but are ready to undertake anything. These philosophers regarded all knowledge as their province, and did __________ despair of governing so great a realm.