What is the best way to deal with sentence 4?

Direction:
The following passage is an early draft of an essay. Some parts of the passage need to be rewritten.
Read the passage and select the best answers for the questions that follow. Some questions are about particular sentences or parts of sentences and ask you to improve sentence structure or word choice. Other questions ask to consider organization and development. In choosing answers, follow the requirements of standard written English.

(1) The last and not the least important way in which science has changed people and made them more civilized is by making them more tolerant. (2) A tolerant person is one who does not interfere with other people, even if he thinks they are wrong, but he is prepared to let them think what they like and say what they think. (3) If he thinks they are wrong he may try to persuade them to believe differently, but he will not try to force them.

(4) This may not seem a very important point, a great deal of the misery of mankind in the past has sprung from people being unwilling to tolerate other people thinking differently from themselves. (5) This intolerance has been particularly common in religious matters. (6) All over the western world, for instance, people have been killed and have tortured other people for not believing the same things as they did or for worshipping god in a different way.

(7) Most religious beliefs are based on faith, and the point about them is that although you may be quite convinced of them yourself, you cannot be sure of persuading other people to believe them too because. (8) Now, it is with regard to beliefs of this kind that people are now more tolerant than they used to be. (9) Formerly if a man thought differently about religious matters from his neighbors, he was very likely to be burnt alive. (10) And if he did not believe in God and had no religion at all he was thought exceedingly wicked and was punished. (11) This is no longer so.