Mumfun said: "I see a correlation between honesty and outrage at the OW..."
Whereas I see a correletion between honesty and treating others the way you'd be treated yourself. So the people who would admit to being under-charged, damaging a vehicle and having found a purse, even if there's no chance of being found out, seem much less likely to hurt a stranger and her children, by having an affair with her spouse.
It's not about sisterhood either - it's about humanity, but of course it exists.
I've certainly said "no", even when sorely tempted, as have many of my friends. Amongst all the other reasons about having too much self-esteem to become an OW and self-protection, a strong reason not to, has been that some poor woman and her children would get hurt. It always surprises me when that's not a bigger deterrent to people, but I am less surprised when it turns out that they are dishonest in other areas of their lives.
As for relying on others' consciences for one's own happiness and that way madness lies, what a strange statement. I don't think it's mad to expect others to treat us with decency and kindness, or to have high expectations of oneself and others. Whereas I think if you expect to be treated badly - and assume that everyone is out for themselves and therefore this lets you off the hook if you behave badly, poor treatment will no doubt come your way.
I've been really lucky in my life to have made and kept friendships with women that have lasted for decades. I realised years ago that I am pretty discerning about who I make friends with and I know I have rejected friendship from women I've met who've adopted a "we're all in it for ourselves" mentality.
Hence it's not surprising that not one of these 20 or so women friends has ever treated me badly or let me down, because although we are very different in character and personality, we share similar values and have high expectations of the way we will treat eachother. Those friendships have been a source of enduring personal happiness.
If a stranger behaves badly to me, yes of course it defies my expectations, but I tend to rationalise that this person would never have become a friend - they would be someone I would never want to know, if their values and humanity are that flawed. So their behaviour doesn't induce madness, just a strong instinct that my life will (and has been) happier than theirs.