What exactly does it mean for a philosopher to be a "modern" philosopher?

So I see that philosophers are categorized as either Ancient, modern, or contemporary. I know where ancient and contemporary fall. Ancient is from the earliest recorded philosophers like Socrates, Plato, Aristotle to around the fall of the Roman Empire. <br><br>Contemporary is from around 1960 onwards. By my count, that makes modern philosophy from the fall of the Roman Empire to 1960. That's a big gap but whatever. <br><br>But what exactly does it mean to be a modern philosopher? To be an ancient philosopher, you have to be like Aristotle. To be a contemporary philosopher, you have to be like people in this sub. What does it mean to be a modern philosopher?