Honesty is the best policy. I believe this in a moral sense, but I've also discovered it to be true in practice -- even when I think I have a good reason for some slight dishonesty, it seems like something happens to nudge me back onto the straight and narrow.
For example, on one occasion, I decide to ride the Metro without a valid ticket, rationalizing that this is better than being stranded in East St. Louis at night without a phone, money, credit cards, or pepper spray. And that happens to be the one time in a thousand when they actually come through the train to check for tickets.
Frequently (although much less frequently nowadays), I decide that it will be less effort to let people continue in some misconception (i.e., that my name is Christy, that I'm the person they meant to call and not a wrong number, that I don't mind eating peppers, etc.) rather than correcting them. I inevitably turn out to be wrong.
On a trip to Denver, I see that the only open window seat is in the exit row, so I change my reservation to that seat. When the flight attendant asks if I can handle opening a 40-pound exit door and assisting other passengers, I say "yes." I mean, I probably could. Maybe. But it's not like it matters anyway. How likely is it that something bad will actually happen on a short flight to Denver?
Ten minutes later, when the alarm starts blaring, smoke starts pouring out of the back of the cabin, and the flight attendant runs down the aisle, I begin seriously reconsidering that decision.
I've heard of people getting caught in their lies before, but I'm the only one I know of who almost got caught in a lie about being capable of opening an exit door. And that's why, for me, honesty is the best policy. Someone seems to be sending me a message, and I think I'd better listen.