Why was natural selection considered revolutionary?

[Pleonasm]

Without evolution you don't have any mechanism for how changes in genes influence populations of organisms over time. Nor do you have any concept of a population's ability to adapt itself to an environment. Those people who don't believe evolution is true generally don't believe that species change over time either.

Why changes occur is due to mutation, which is irrelevant. Natural selection is a self evident, truistic account of life with or without mutation. A world in which there was no mutation wouldn't change the fact that those that are better at surviving, survive, the rest don't, and are unable to reproduce.

 

[Drakkith]

A world in which there was no mutation wouldn't change the fact that those that are better at surviving, survive, the rest don't, and are unable to reproduce.

I agree in general. But that's not the issue here. Of course it's true that, given certain laws or rules, only certain consequences can result from laws and rules. This isn't truism. A truism is defined as a statement that is obviously true and says nothing new or interesting. Natural selection is, importantly, not a statement. It is a process undergone by populations of organisms, with all the complexities and subtleties of a widespread real world phenomenon. The statement that organisms that are better at surviving will survive and pass on their genes, while the others won't, is an extremely simplified description of this process. It is absolutely not a truism.

The statement that a team which scores more points will win the game is self evident, as it follows directly from the rules of whatever game you're talking about. But it is also not a truism.

 

[Evo]

The OP's question has been repeatedly answered, so to stop beating a dead horse, thread closed. Thank you all that answered his/her question.