Morals are sort of the rules of a 'group'.
Sarah (the Psycho One) in her posting implies that morals are derived from social 'opinion'; that is, they are the rules a society imposes on members to 'get along'. That is a reasonable way of looking at this, but has no permanence. For instance, 'society' around the world agreed that slavery was okay - as long as it was happening to someone else. Then some pack of radicals starting talking about the 'worth of the individual' and finally got it outlawed. (Except in places where those 'radicals' aren't allowed.)
The point is, as long as the ordaining body of the moral code is society, the moral code is flexible and shifts with the tide of public opinion. We see that right now in the United States - probably other places as well, but I don't get around that much.
Syd said:
Do theists think that atheists will suddenly abandon their morals randomly at some later date?
I cannot speak for all 'theists' (as you cannot speak for all 'agnostics') but I don't think atheist moral changes are 'random' in the sense of 'sudden and without warning'.
Take a look at the popular view (in the U.S.) of pregnancy out of wedlock: Sixty years ago, it was unthinkable. Now, it's more or less the way things happen. That change of view is largely among the non-Christian community. Sixty years ago it was more than an issue of 'improper sexual conduct', it was also a matter of economics and the effect on the culture. Now, it isn't a big deal.
This is a shift in moral outlook by people who are functionally atheist or agnostic. The hardcore Christian believers still believe it to be wrong and should be avoided. My point is, that was a shift in moral view, but not sudden or without warning. (Was it random?)
Allow me a seeming digression. How does a modern society know a certain action is 'against the law'? One remembers the oft-coined phrase, "There ought to be a law!"
Something is 'against the law' if and only if there is a statutory code section defining that action as a crime. (Again, this is in the U.S.; I know of some dictatorial states where a 'crime' is anything the dictator deems a crime.) One has to have a 'standard' against which to measure. For the U.S. Federal Government, the standard is the "United States Code" (USC) which has the 'laws' listed. Each state has it's own list of penal code, business code, health code and so forth.
So how does one know if something is 'moral'? By checking against a code, it seems. When young, one asks a parent about such decisions. One trusts a parent will know. (This of course is a general statement; I am aware some parents do NOT know right from wrong, or do not care. I'm not trying to offend any one from such a situation.)
The moral code of the Creator God has existed long prior to the establishment of Christianity. It is recorded in the Bible, although not as clearly as some seem to demand. Oddly enough, it is in fact the moral code of the founder of Christianity.
So. Yes, atheists can be and are 'moral' persons. Most of the atheists I know are honest, truthful and well mannered. (There are a couple who are untrustworthy narcissists, but I've met Christians of the same ilk...) The problem is, how long will that current standard of morality exist? In the past three hundred years, humanity has changed from 'slavery is okay' to 'slavery is wrong'. When will it change back?