There's an old expression that says the world needs fewer people who know how to fix the economy and more people who signal for their turns.
It speaks to a tendency most of us have. We have no problem declaring that we know what the president or the governor or Andy Reid ought to be doing, but we neglect the little things we could do ourselves to improve the world.
One of those things we could do - and only we can do - is give blood.
There's no substitute for human blood. It can't be manufactured. Medical researchers have found ways to extend the usefulness of blood - splitting it into red cells, platelets and plasma, using refrigeration to store it - but the blood supply is still dependent on one person at a time giving one pint at a time.
Each pint of blood can save up to three lives, and most of us - 90 percent - will need a blood transfusion at some point.
Because blood is perishable, the supply needs to be constantly refreshed, and this summer, that's just not happening.
Summer is usually a slow time for blood donations, since high school and college students are not in school and many donors take vacations. This year, supplies of blood donated through the American Red Cross are at a 15-year low.
Maybe it's because the old model for blood donation included industrial workers who could donate as part of their shift and service organizations that ran regular blood drives for their members. Most of those industrial jobs have disappeared, and service organizations are having a hard time recruiting members.
Many people work more than one job, or are so busy with the demands of parenting and working that donating blood is no longer an automatic part of their lives.
But none of that lessens the demand for blood.
In New Jersey, 60 percent of the population is eligible to give blood, but less than 4 percent of adults actually give each year. As a result, the state has to import blood from other states. The state Department of Health and Senior Services says that in 2010, New Jersey imported nearly 50,000 pints of blood.
So why don't more people give blood? Some may fear blood-borne diseases, but it is impossible to contract a disease from donating. Some may think it is difficult or painful, but most donors say it is neither.
Healthy people older than 17 who weigh at least 110 pounds can give blood every 56 days.
American Red Cross representatives say the No. 1 reason people don't give blood is that they've never been asked.
Consider yourself asked.