Computer is never wrong.

Yesterday, one of my co-workers told me, "Peter, there is something wrong with my computer. It's very very weird. I am sure my code is correct, but it doesn't work!"

I check his code and found that he misspelled a variable.

After that, I made some comment. "In my experience, computer is never wrong. It's always people who made mistakes. And that's why I decided to major in computer science. I thought the world is a unfair place, but in computer, 1 plus 1 is always equal to 2."