system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: "Scratch a pessimist and you find often a defender of privilege. -William Beveridge"
gpt
A pessimist is someone who has a gloomy outlook on what will happen in the future. People who are societally hopeful hope for good things for those in need, but a pessimist doesn't share that hope. 

You say to the pessimist: "Hey, let's do this thing to make society better!" and the pessimist says "No, let's not do it, it won't work." Then the status quo is kept as it is and everyone keeps their privilege.