If it were due to new facts and information, sure, but a lot of time the "new" principles appear to be self-interest biases manifesting. Also, if your principl

If it were due to new facts and information, sure, but a lot of time the "new" principles appear to be self-interest biases manifesting. Also, if your principles are likely to change quickly, it's probable that they haven't been thought through very thoroughly to begin with. It's not like you have to wait for situations to actually arise to consider them.