What is defined in the image is actually nihilism. Silly, they've confused their terms. It's a common mistake that needs to be addressed as it pops up. Atheism is not an ethical philosophy. It's simply a lack of belief in gods. The ethical implications of this vary from person to person, but most atheists do not agree with nihilism. Many atheists believe that morality is an inherited trait that helps social animals thrive, so even without the threat of eternal punishment, morality is very relevant. I think it is more relevant, since this is the only life we get, and we can't just kill a goat or mumble some incantations to make our wrongdoings okay.