Read the following passage carefully and answer the questions that follow:
A person who takes the trouble to form his own opinions and beliefs, will feel that he owes no responsibility to the majority for his conclusions. If he is genuine lover of truth, if he is inspired by the passion for seeing things as they are and an abhorrence of holding ideas which do not confirm to facts, he will be wholly independent of the assent of these around him. When he proceeds to apply his beliefs in practical conduct of life. The position is different. There are then good reasons why his attitude should be less inflexible. The society in which he is placed, is an ancient with composite growth. The people, from whom he dissents have not come by their opinions, customs and institutions by a process of mere haphazard. These opinions and customs all had their origin in a certain real or supposed fitness. They have certain depth of root in the lives of a proportion of existing generation. Their fitness for satisfying human needs may have vanished and congruity with one another may have to come an end. That is the only one side of the truth. The most zealous propagandism can not penetrate to him.
In common language, we speak of a generation as something possessing of a kind except unity, with all its parts and members homogenous, yet plainly it is not this. It is a whole, but a whole in a state of constant flux. Its factors and elements are eternally shifting. It is not one but many generations. Each of seven ages of man is neighbours to all the rest. The colours of the newest recruits is forming to each its traditions, its tendency and its possibilities. Only a proportion of each can have nerve enough grasp the banner of a new truth and endurance to bear it along rugged and untrodden ways.
Then we must remember the stuff of which life is made. We must consider what an overwhelming preponderance of the most tenacious energies and most concentrated interests of a society must be absorbed between material cares and the solitude of the affections. It is obviously unreasonable to lose patience and quarrel with one’s time because it is tardy in throwing off its institutions and beliefs and slow to achieve the transformation which is the problem in front of it. Men and women have to live. The task for most of us is arduous enough to make us well pleased with even such imperfect shelter as we find in daily use and want. To insist on a whole community being made at once to submit to the reign of new practices and ideas that have just begun to commend themselves to the most advanced speculative intelligence of the time-this, even if it were a possible process, would do much to make life impracticable and to hurry of on a social dissolution.
What is the hard task, the author is reforming to in the third paragraph?