In my favorite comic strip, "Peanuts," by Charles Schulz, Lucy asks Charlie Brown what day of the week he likes best. For the next few frames, we see Charlie thinking and thinking. Finally, he says, "You know, I've always been kind of fond of tomorrow."

For once, I have to disagree with good old Charlie Brown. My favorite day is today, because every morning when I wake up, today is what I have to work with.

With the new year upon us, I have a challenge for you. Stop worrying about that which you cannot control.

Many years ago, this advice came from Robert Jones Burdette, an American humorist and clergyman: "There are two days in every week about which we should not worry, two days which should be kept from fear and apprehension." Can you guess which two days he's referring to?

Various versions by numerous authors expanded on Burdette's answer:

"One of these days is yesterday with its mistakes and cares, its faults and blunders, its aches and pains. Yesterday has passed forever beyond our control. All the money in the world cannot bring back yesterday. We cannot erase a single word we said. Yesterday is gone."

"The other day we should not worry about," he continued, "is tomorrow with its possible adversities, its burdens, its large promise and poor performance. Tomorrow is also beyond our immediate control. Tomorrow's sun will rise. Until it does, we have no stake in tomorrow, for it is yet unborn."

And then we get to the meat of the argument:

"This leaves only one day — today. Any person can fight the battles of just one day. It is only when you and I add the burdens of those two awful eternities — yesterday and tomorrow — that we break down. It is not the experience of today that drives people mad — it is remorse or bitterness for something which happened yesterday and the dread of what will happen tomorrow."

Let that sink in for a minute. Today is the only day we can take action. Sure, we learn from yesterday. And of course, we plan for tomorrow.

But unless we approach each day with a renewed positive outlook, we are wasting enormous potential.

Use every tool in your kit to build on the traits you need to think and act positively each day. These include reliability, communication and listening skills, cooperation, loyalty and humor, among other qualities. If you are concerned that you are weak in any of these areas, resolve to improve. Make a New Year's promise to yourself to not waste another minute on negative thinking. Make every today better than yesterday.

I had the honor of knowing Dr. Norman Vincent Peale, who endorsed my first book, "Swim With the Sharks Without Being Eaten Alive." Peale happened to have a bestseller of his own that you have probably heard of: "The Power of Positive Thinking." That book, which he wrote in 1952, has sold more than 5 million copies. I recommend it as an essential volume on every businessperson's bookshelf.

Among the gems you will find in "Positive Thinking":

• "You do not need to be a victim of worry. Reduced to its simplest form, what is worry? It is simply an unhealthy and destructive mental habit."

• "The way to happiness: Keep your heart free from hate, your mind from worry. Live simply, expect little, give much. Fill your life with love. Scatter sunshine. Forget self, think of others. Do as you would be done by. Try this for a week and you will be surprised."

• "When you expect the best, you release a magnetic force in your mind which by a law of attraction tends to bring the best to you."

• "Believe in yourself! Have faith in your abilities! Without a humble but reasonable confidence in your own powers you cannot be successful or happy. But with sound self-confidence you can succeed. A sense of inferiority and inadequacy interferes with the attainment of your hopes, but self-confidence leads to self-realization and successful achievement."

Peale's writings will inspire you to look at life through a more positive lens. Take time in the new year to read — or reread — this valuable resource. Trust me, I dust off my well-worn copy whenever I start to worry about yesterday and tomorrow instead of celebrating the opportunities I have today.

Mackay's Moral: Have a positively Happy New Year!

Minneapolis businessman Harvey Mackay can be reached at 612-378-6202 or e-mail harvey@mackay.com.