Heraclitus was a very smart man who lived a long, long time ago in Greece. He thought a lot about the world and how everything in it works, and he came up with some very interesting ideas.
One of his most famous ideas was that everything is always changing, all the time. This might sound a bit strange to us, because some things seem like they don't change much at all. But Heraclitus believed that even things that seem the same on the outside are changing on the inside.
He explained this by saying that everything is made up of tiny bits, kind of like little building blocks. These bits are always moving and changing, and they come together to make all the different things we see in the world.
Heraclitus believed that this constant change is a good thing, because it keeps the world interesting and alive. He also believed that we humans need to change and grow too, so we can keep up with the changes in the world around us.
In fact, Heraclitus said that the only constant in life is change. He meant that no matter what happens, everything will keep changing, and we need to be ready for that.
So, in summary, Heraclitus was a very smart man who thought that everything in the world is always changing, and this is a good thing because it keeps things interesting and alive. He also believed that we need to keep changing and growing too, so we can keep up with the changes in the world around us. And he said that the only constant in life is change.