When it comes to personal conduct, we need anchors to set the standards that govern our behavior. With free-floating standards our behaviors too often have a radius that encompasses what we would also deem as unacceptable. An example illustrating this idea is with R-rated movies.
I said it just recently on here, but I think there are some R-rated movies that are worth watching. Sometimes they get the ratings because of swear words, violence, or suggestive content, among other things, but the sometimes messages or the stories that they deliver are wholesome and even uplifting. The trouble, however, is that when I start allowing myself to have the free-floating rule of just being selective rather than taking a hard-line stance, it's so easy to allow my judgment to drift and watch other movies that are inappropriate. Giving an inch often becomes a mile in what becomes permissible. Some people might be able to get away with it, but I think for myself I'm just not smart and disciplined enough to allow leeway when it comes to this kind of thing (just to be clear, this is a personal decision for me and might not be necessary for other people).
I started thinking about this recently with respect to a girl that I know. In the midst of a conversation about our dating experience from when we were younger, she mentioned how she and her friends used to bait guys into liking them, only to drop them and move on to the next guy. I remarked how mean that seemed, and I thought that her response would be something like how that was a different time and she has since seen the folly of her ways. Instead, she snidely replied, "you can't be cruel to guys that are heartless."
That answer just never sat right with me. Regardless of what another person is like, that shouldn't change the way you treat them. Whether they invite poor treatment, or they even deserve it, there are certain boundaries that you just shouldn't ever cross, if only because it expands the realm of what you think is acceptable behavior. In talking with a friend last night about this subject, she said that your behavior shouldn't be guided by what other people do, but by your own principles. Because this girl (the former, not the latter) let her conduct be dictated by her circumstances, eventually it turned into whatever served her purposes, so even more recently when she has been dating decent guys, she treats them with little regard. This idea has been expressed in many different ways, but I like how Phillip Seymour Hoffman's character expresses it in the movie Mission Impossible III, "You can tell a lot about a person's character by how they treat people they don't have to treat well."
In the end, the anchors that we choose to use are the principles that govern how we act. Without principled behavior, we allow ourselves to be tossed about by the waves of our circumstances. Rather than having an anchor that secures us to a specific code of conduct that we can never venture away from, we have only floating buoys that drift and are tossed until eventually they no longer even mark the ground where we thought we were standing.