Technically, anyone can say, "I never do anything stupid," as it is a statement that can be expressed by anyone with the ability to speak or write. However, whether that statement is true or not is subjective and depends on the individual's self-awareness and judgment.
In reality, everyone makes mistakes and does things they might later consider unwise or "stupid." Making errors or poor decisions is a natural part of being human, and it's how we learn and grow. Claiming to never do anything stupid might indicate overconfidence or a lack of self-awareness.
It's essential to recognize our fallibility and be open to learning from our mistakes. Embracing our imperfections and being willing to grow from them is a more constructive and honest approach to personal development. So, while someone can say, "I never do anything stupid," it's more realistic and beneficial to acknowledge that everyone makes mistakes and strive to learn from them.