If you read the comments section at this Debunking Atheism post you will see that Daniel Morgan has taken a stab at defining good and evil.  (Apparently, Loftus still cannot do so.)

Morgan says:

Similarly, let me put forth a definition of “good” and “bad” to create a very simple moral framework:
“good” is the state of actions, events, and natural conditions which minimizes, if not reduces altogether, babies being slaughtered in genocidal warfare

“bad” is the state of actions, events, and natural conditions which does not minimize, nor reduce altogether, babies being slaughtered in genocidal warfare

But this is, of course, a completely arbitrary claim.  I could just as easily respond with: “‘Good’ is people with brown hair, ‘bad’ is people with blond hair.”

Morgan then “proves” his point by saying:

Of course, the presupps can disagree with me on the definition of good and bad here, which I have purposely restricted to the case of infanticide, as the result of genocidal warfare. If they do, though, I would love for them to explain how my definitions of “good” and “bad”, as objective markers, fail.

As much as atheists love to point out that it’s improper for theists to make them prove a negative, they sure like to insist on theists proving lots of negatives.  Morgan can’t provide evidence for his definition of “good” and “evil” so he instead relies on, “You can’t prove it’s wrong.”

But of course I don’t have to prove it wrong.  Morgan has to prove his definitions right.  And that is something he cannot do in his atheistic worldview.

And that is the point that the atheists keep missing.  We are not debating what behavior is or is not good or evil–we are debating how one knows what is good or evil.

Before Morgan’s non-answer of the question, Joe Holman attempted to provide a reason for saying something is evil by saying:

…nerve cells being rended, ripped, or torn by a hungry predator, sharp metal objects being plunged into soft bellies like a pearing knife through a tomato, a bullet penetrating a lungsack and causing a slow, painful death…these are things that all human and animal kinds realize are wrong except in the most dire of circumstances.

But this is absurd.  Animals don’t know anything about sharp metal objects, bullets, or any of the like.  They are not cognizant of these things.  But even if they were, it would not magically make such things “immoral.”

Holman seems to say (as Loftus has claimed before) that pain = evil.  But he cannot point to nature for this fact.  Animals kill each other all the time.  I’m quite sure the zebra thinks it’s painful to have a cheetah attached to his hamstring, but that doesn’t make the cheetah evil for killing the zebra.  Similarly, this argument ignores the fact that massochists exist who actually enjoy pain.  Holman’s argument doesn’t prove his morality.

The atheists are still left holding on to stolen concepts.