Some years ago I heard an analogy that resonated with me.  It was a description of learning something – some piece of information about a person’s character – that was so negative, so vile, that no matter what else you knew about that person, you instantlyunderstood the core of the person in question.  There is, in fact, a folk-wisdom saying that illustrates this concept, which I first heard on a talk radio show: “That tells me everything I need to know about him.”  Ironically, the talk radio host from whom I first heard this expression was revealed to have done something I consider so vile that, even before he was taken off the air, I realized that deed (plus his “Yeah, so what?” attitude) told me everything I needed to know about him – and I stopped listening… and having stumbled across his new broadcast home while channel-surfing, I still refuse to listen to him.
Before I dig into this, I want to be clear – nobody is perfect.  We all have our flaws, being human beings, and need to be forgiving and tolerant.  We all struggle with weaknesses and sin, and while Jewish I’ve found I like the instructional concept of the Seven Deadly Sins (and the other side of the coin, the Seven Cardinal Virtues), and am convinced that while all these are human weaknesses, each person has their “one sin” with which they wrestle as their dominant weakness.  And in that struggle with and – hopefully – victory over it do we demonstrate that we are more than a collection of chemicals and cells, but sentient creatures striving to improve ourselves.
So… this analogy goes as follows:
Imagine you have two cups.  One contains the purest, clearest, most wonderful water possible.  The other, raw sewage.  When you mix the two, you get sewage.  The same for a cup of sewage and a pitcher of water, or a barrel of water.  Regardless of the size of the pure water container, the sewage contaminates it.
This became the root of what I refer to as “The Rules of Sewage” in regards to a person’s character.  This one is the First Rule of Sewage, The Non-Proportional Rule of Sewage.  It means, as the saying above goes, that you can sometimes learn a thing about a person that taints the entirety of their personality – e.g., a person beats their spouse.  It doesn’t matter what else they are, what acts they do, they are polluted by that one thing.
This simmered in my mind over a couple of years, and I started to formulate other Rules of Sewage.  Each was based on the same base concept – mixing water and sewage.  Thus far I’ve come up with six.
The Second Rule of Sewage is the Non-Compartmentalized Rule of Sewage.  You cannot pour a cup of sewage into a container of water, and have it only remain in the place you poured it.  Bad character leaks into other elements of character.  E.g., a person who cheats on their spouse – thus breaking a sacred oath – cannot be counted on to keep an oath in any other part of their life.
The Third Rule of Sewage is the Immersive Rule of Sewage.  Imagine an edible fish taken from that pure water, placed in sewage, and somehow surviving – no matter the fish’s immune system and other defenses, it will become contaminated.  No matter how pure you are to begin with, if you are surrounded by bad people or bad content, it will start to affect you.  E.g., a good, honest person who goes to work in a place with bad ethics and stays there – for whatever reason – will sooner or later find they are making compromises to their own character and standards, and rationalizing their doing so.  (And this is, of course, the root of the proverb “Birds of a feather, flock together.”)
The Fourth Rule of Sewage is Irreversible Rule of Sewage.  Simply put, it’s a lot easier to mix the sewage in and ruin the water than reversing the process.  While people are certainly capable of change, it takes deliberate effort to do so, and usually also an ongoing awareness and maintenance of that change to avoid slipping back to whatever factor is being avoided.
The Fifth Rule of Sewage is the Odiferous Rule of Sewage.  Sewage, to put it bluntly, stinks like sh*t.  Bad odors like that can be covered up or contained, but not forever.  Sooner or later the malodorous item in a person’s character will out, and be readily apparent.  This actually ties in with…
The Sixth Rule of Sewage, the Reactive Rule of Sewage – when faced with a tank of sewage, normal people react negatively.  And while a person learning something about another (ref: Rule One) won’t physically turn their head away and scrunch up their face in disgust, I believe the plain truth is that upon learning of such a think will cause a decent person to dissociate – to whatever degree possible – from the other.  Failing to do so, or worse expressing approval, could be considered an example application of Rule One about them too.
In putting this concept “out there” it will be interesting to see if other Rules of Sewage develop in the comments.