If you're lucky, your friends trust you. They will have to focus on the credibility of your ideas, not on the fact that you are a kind-hearted soul who always tracks down the owner of the extra quarter you found in the soda machine.
Logic is the tool writers use to establish their credibility with readers.
When a writer bases an idea or proposal on weak logic, we say that the writer has committed a logical fallacy . Rhetorically speaking, logical fallacies are the equivalent of thin ice. When this ice cracks, your argument is likely to fall through. And once you find them, do your best to get rid of them. No one requires me to buy certain groceries before I can leave the supermarket.