Why are humans the dominant species on Earth when we aren't as strong or intelligent as other animals?

This question is for all you intelligent chambersors out there. As a human I've always wondered why we are the dominant species on Earth. I'm sure many of you have wondered this same question at some point in time. I've seen humans crush other animals in a physical fight with just a baseball bat or a knife. I've also seen a human use a tool and accomplish a task much easier than an animal. This made me think, why aren't other animals stronger or smarter than us? I've watched some animals outsmart us and it's quite impressive. So, why aren't we as smart as an octopus or as strong as a bear or lion? I just don't understand. Please help me out with your answers.