[Last Visible Dog]

Because it's as certain as a scientific theory can be. I think from your question that you might not understand the meaning of the word "theory." Hint: it doesn't mean shaky, unproven or a guess of any kind

I hope you are not trying to imply "life emerged from the chemical soup of early Earth" is "as certain as a scientific theory can be" - if so, that is total poppycock. This thread is a about the origin of life, not Darwinist Evolution which BEGINS at a point in which life already exists and the mechanism to genetically pass on extremely complicated information has already been created.

[Last Visible Dog]

"if so, that is total poppycock"

...and it makes a great snack

[highball]

You're right - Darwinism has no comment on the origins of life. That's another subject.

Evolution does, however, accurately describe what happened to that life. In two hundred years of trying, anti-Darwinists have not been able to come up with their own theory that addresses the evidence in anything remotely close to the scientific method. Wonder why that is?