What are some general quotes I can memorize for my essay?

I have an essay to write this week, and it is a test so I can't use the Internet. I wanted to memorize some general quotes that could be used for a variety of different easy topics because I won't know what the topic is until the day of the test. It will probably be something losely based on society, roles in society, the good of society vs individual or stuff like that but I'm not sure! So do you know any good general quotes? Especially ones by well known people? (like for example Gandhi, Charles dickens or mother Theresa) Thanks!