The Earth is fine and there's no way we can destroy all life or even most life on it at the scale it's happened before.
We can make ourselves extinct rather easily though and that's the problem you should have asked about.
Reductionist and proud of it.
Being ignorant is not so much a shame, as being unwilling to learn. Benjamin Franklin
Chase after the truth like all hell and you'll free yourself, even though you never touch its coat tails. Clarence Darrow
A person who won't read has no advantage over one who can't read. Mark Twain