Moving average, Day Trade, bull spread, derivatives, Earnings before interest, taxes, depreciation and amortization (Ebitda), dividends, technical analysis, fundamental analysis... There are many terms and areas of study within the investment market. However, one thing has always caught my attention since 2005, when I made my first investment in variable income. I observed that people were mesmerized with the market and with the possibilities of "easy" earnings and neglected a fundamental aspect in investments, the emotional and psychological side. In this sense, I was enchanted by the Stoic philosophy, which is pointed out by many as a practical philosophy, that is, it proposes instruments that will not only generate abstract reflection but that have the potential to effectively contribute to your daily lives through thinking techniques that can be adopted. Therefore, the purpose of this book is to raise just a few elements of this very important topic, full of nuances and particularities. If I manage to pique my dear reader's curiosity to study more the emotional aspects in decision making, as well as delve into Stoic philosophy, this work will have fulfilled its role.