Investing without understanding is a common and costly mistake, even among highly educated individuals. The article draws a parallel between the biblical plague of darkness and the confusion investors face when they lack clarity about their investments, leading to poor decisions in times of market stress. It emphasizes the importance of due diligence, preparation, and active engagement, highlighting that true financial independence is achieved through disciplined decision-making and a clear understanding of one's investments. Research shows that investors who chase trends or invest in complex products they do not comprehend consistently underperform, underscoring the need for simplicity and transparency in financial planning.