"La cause fondamentale des problèmes dans le monde aujourd'hui est que les stupides sont sûrs d'eux tandis que les intelligents sont pleins de doutes"

Simplified Meaning:

People who don't know much often think they're always right and speak loudly about their opinions. Because they're so sure of themselves, they can spread their ideas quickly. On the other hand, people who know more tend to question themselves and think carefully before saying anything. This makes them quieter and less likely to share their thoughts as forcefully. Imagine a classroom where a student who didn't do the homework shouts out the wrong answer confidently, making the whole class think it's correct. Meanwhile, a student who did the homework and knows the right answer might hesitate to speak up because she's unsure. This creates confusion and can lead to the wrong information being accepted by everyone. In life, it's better to try and listen to those who take time to think about their answers, even if they're not as loud or sure, because they likely understand things more deeply. Being aware of this can help you make better decisions by valuing thoughtful and informed advice.