I don't have just one, but I have one in each area of my life which is important to me.

I have a family, and I just make sure to love them as much as I can. I have given up careers to spend more time with my kids. There's really no limit to the amount of love a child can have.

In business, you've got to be shrewd, but honest. Listen to your gut ONLY AFTER you ran the numbers multiple times. If you are not good at making decisions, stay away from business. Honesty will win you more sales/contracts than dishonesty. Especially since I've heard it said that a customer is 23 times more likely to spread a bad review, than a good one.

I've got one for preventative health: "Let your food be your medicine.", and one for general mental well-being and health: "Everything in moderation." They are pretty self-explanatory, but if you have a personality which indulges in excess, then you will need to come to terms with that at some point in your life.

Take care of your property. Whether it is a country estate or a shitty beater car. The state in which your possessions are in, reflects directly onto you as a person. You might not care about what others think of you, but it can be a powerful way to look at yourself from outside yourself. It is important to gauge yourself because as you age, you change so imperceptibly, that one day you might wake up as a bigoted lunatic because you never took the time to put your physical and material life in order. I always feel better after cleaning out my garage and shop, and having a sale to get rid of unwanted items, and sometimes garbage.

No matter what, above all else, never fall into the ego-trap which is inherent in a physical life on this planet. Ego-traps are when a person adopts a persona to become a part of a certain reality. You see it a lot in junior high, high school, and college where in each of these situations, it serves as a psychological liferaft when navigating through tough times like puberty for example. The problem is when a person becomes addicted to that persona to where it affects there life adversely. It is my personal belief that cultures evolved from the competition to attract mates. People tend to adopt all sorts of ridiculous personas when they get trapped in the ego-trap. Most are harmless, many are not... Life is basically a non-stop ego-trap, which keeps you from being truly happy. Find what it is that makes you happy, and build your life around that. For me, and many others, it was starting a family. Now that is everything to me. The bottom line is that ego-traps are a waste of time, and they keep you from evolving as a conscious human being.