When Did Life Appear?

When did life appear on the earth? Was it billions of years ago, or was it something like 6,000 years ago? The Smithsonian doesn't know (pictured). They use the word "probably" when it comes to when life began, which is probably the most-used word when it comes to the theory of evolution. I use the word "probably" when it comes to it being the number one word, because I really don't know. I could be wrong.

Imagine stepping into a plane that you believed was "probably" safe, or into an elevat