"C’est la marque d’un charlatan d’expliquer"

Simplified Meaning:

When someone who isn't really an expert pretends to know a lot, they often explain things in a way that sounds fake or overly complicated. Imagine a person who says they are a car mechanic but doesn’t really understand how cars work. Instead of fixing the car, they talk a lot about engines and parts, hoping you’ll believe they're knowledgeable. This is because they want to hide their lack of real skills. In history, there might be a speaker who gives speeches about things he doesn't really know just to trick people into thinking he is wise. For example, a person might pretend to know everything about healthy eating and give lots of fancy advice, but they actually don't know what they're talking about. To avoid being fooled by such people, one should be careful and think about whether the person clearly understands what they're talking about or if they just use big words to confuse others. This also means it's important to learn enough about different topics so you can tell the difference between a real expert and someone who is just pretending.