As much as I like to travel, I am never sure how much to pack. When my wife and I take off for a week long vacation, we do our best to keep a week’s worth of possessions down to one suitcase. That is the goal. There is never a guarantee it will happen.

Packing is determined by two contradictory principles: how do we move quickly? How can we be prepared for every contingency? How many pairs of pants can I take, or in my wife’s case, how many pairs of shoes? Should we pack a sweatshirt? Does it rain in New Mexico? How about a suit jacket, in case our hosts take us out to dinner? And given that we booked a very small rental car, will the suitcase fit in the back?

Packing is an art form. There are experts throughout the internet, suggesting “How to pack like a Ninja.” They offer great advice…