Someone once asked a great philosopher what he would rather have -- a gift of money or a gift of friendship.

“Friendship,” replied the philosopher, “because money is spent, but friendship can last forever.”

Maybe this is why our greatest wealth is not measured in terms of riches but in our relationships. Friendship is the cement that holds the world together.

Friendship is so important we celebrate it several times during the year. February is International Friendship Month, and Old Friends, New Friends Week is the third week of May.

The first Sunday of August was declared as a U.S. holiday in honor of friends by Congress in 1935. Since then, World Friendship Day is celebrated every year on the first Sunday in August.

As novelist George Eliot describes it: “Friendship is the inexpressible comfort of feeling safe with a person, having neither to weigh thoughts nor measure words.”

That’s a fancy definition for what we all know is central to our happiness. I can’t imagine a life without friends.

I cherish the friends I’ve known since childhood. Along the way I’ve met friends through business, travel, sports and the community. They enrich my life and, perhaps just as important, know they can count on me to be there for them.

One of the best books I’ve ever read and learned valuable lessons from is Dale Carnegie’s “How to Win Friends and Influence People.” Carnegie wrote: “You can make more friends in two months by becoming interested in other people than you can in two years by trying to get other people interested in you.”

To drive home the point, Carnegie tells how dogs have learned the fine art of making friends. When you get within 10 feet of a friendly dog, it will begin to wag its tail. If you take the time to pet the dog, it will become excited and lick and jump all over you to show how much it appreciates you. The dog became man’s best friend by being genuinely interested in people.

Last September, we lost an NFL legend in Chicago Bears running back Gayle Sayers. I’m old enough to have followed his short but brilliant career. Yet what I remember most about Sayers is the memorable friendship he had with a teammate named Brian Piccolo, memorialized in the movie “Brian’s Song.” Sayers was black, and Piccolo was white. They were roommates when the team traveled, which was a first for race relations in professional football.

The two became very close friends and challenged each other. When Sayers hurt his knee, Piccolo helped his friend through a grueling rehabilitation. During the 1969 season, Piccolo was diagnosed with cancer and was in the hospital more than on the playing field. Sayers was often at his bedside.

After that season, Sayers was awarded the prestigious George S. Halas Courage Award as “the most courageous player in professional football.” Sayers, Piccolo and their wives had made plans to go together to the annual Professional Football Writers’ Banquet in New York, but Piccolo was too sick to attend.

At the banquet, Sayers struggled to speak and said: “You flatter me by giving me this award, but I tell you here and now that I accept this award not for me, but for Brian Piccolo. However, Brian cannot be here tonight. He is too ill. But Brian is a man who has more courage than any of us here tonight. I love Brian Piccolo, and I’d like you to love him too. When you hit your knees tonight, please ask God to love him too.”

Shortly after that memorable night, Brian Piccolo died. These two tough football players had developed an unforgettable friendship.

Mackay’s Moral: Good friends are like toothpaste. They come through in a tight squeeze.

Even though President Abraham Lincoln was in office during one of the most turbulent times in American history, he became famous for his ability to use humorous stories and anecdotes to make a point. His talent often saved difficult situations from escalating to deep divisions.

To explain why he used stories so frequently, Lincoln said: “I believe I have the popular reputation of being a storyteller, but I do not deserve the name in its general sense, for it is not the story itself, but its purpose, or effect, that interests me.”

Lincoln explained: “When I tell a funny story, it has the same effect on me that I suppose a good square drink of whiskey has on an old toper. It puts new life into me. The fact is, I have always believed that a good laugh was good for both the mental and the physical digestion.”

One tale Lincoln was fond of telling on himself was about two Quaker women in a railway coach who were overheard in a conversation about Lincoln and Jefferson Davis, president of the Confederacy.

“I think Jefferson (Davis) will succeed because he is a praying man,” said the first.

“And so is Abraham a praying man,” said the other woman.

“Yes,” said the first, “but the Lord will think Abraham is joking.”

Lincoln was determined from his teenage years onward to advance his general knowledge. He pursued a rigorous program of reading, study and self-improvement, often by the light of an oil lamp. Lincoln’s law partner would later describe his ambition as “a little engine that knew no rest.”

In 1841, 20 years before he became president, Lincoln doubted whether his life would amount to anything. He confided to a friend, “I would be more than willing to die, except that I have done nothing to make any human remember that I have lived.” His bouts of melancholy were well-known, but even during those challenges, he maintained a wry sense of self-deprecation.

When others tried to insult Lincoln, as during his famous debates with Sen. Stephen Douglas, the orator pointed out that Lincoln used to run a store where you could buy whiskey. But Lincoln turned the tables quickly: “It is true what Mr. Douglas said, that I did run a grocery store, and I did sell goods including whiskey.

“But I remember in those days, Mr. Douglas was one of my best customers. Many a time I have stood on one side of the counter and sold whiskey to Mr. Douglas on the other side. But the difference is that I have left my side of the counter, but Mr. Douglas still sticks tenaciously to his.”

Lincoln had to endure much vicious criticism as president. He accepted that it went with the job, explaining: “If I were to try to read, much less answer, all the attacks made on me, this shop might well be closed for any other business. I do the very best I know how, the very best I can, and I mean to keep doing so until the end. If the end brings me out all right, what is said against me won’t amount to anything. If the end brings me out wrong, 10 angels swearing I was right would make no difference.”

Amid multiple challenges of the Civil War, Lincoln once told a group of scaremongers the story of a young boy who accompanied his father on a hunting trip. While sleeping on the mountainside, the boy awoke to see a meteor shower. Frightened by the sight, he ran to his father and woke him up, pointing at the sky.

The father looked at his son patiently and said, “Son, don’t be concerned with shooting stars. Keep your eyes instead on the fixed stars that have long been our guides.”

The moral of that story is as true today as it was 160 years ago.

The president was once criticized for referring to the Confederates in kind terms. A woman asked him how he could speak so generously of his enemies when he should rather destroy them.

But in characteristic fashion, Lincoln demonstrated his strategy. He answered her, “Why, madam, do I not destroy them when I make them my friends?”

Isn’t it interesting how the more things change, the more they stay the same? We are still learning from Abraham Lincoln.

Mackay’s Moral: America is a better place because Abraham Lincoln helped shape it.

I wouldn’t be where I am today without Larry King. I’ll never forget the first time I met Larry. I was in New York to tape a television commercial for my first book, “Swim With the Sharks Without Being Eaten Alive.” I was a total unknown, a first-time author.

There, on the set, in living color, was Larry King, holding up his latest book and taping his own commercial.

We were introduced briefly when he finished. Then it was my turn on set. Ten minutes later, the director said we were done, and I headed for the elevator, where I saw Larry waiting. We made a little small talk on the way down. His stretch limo was curbside. I started to hail a cab.

He motioned to me and said: “Which way are you headed, kid?” and offered me a ride to my hotel.

I had five minutes to make an impression. Half the people might talk about themselves. The other half might mention how much they love Larry. However, my father taught me an important networking rule -- What can I do for the other person? How can I add value to his or her life?

I didn't know Larry's background. I didn't know a single characteristic, interest or goal that he and I had in common. Except the reason we had both gone to the studio.

I said: “Mr. King, I hope I'm not overreaching here, but I assume you, like I, showed up at that studio because we'd both like to sell a ton of books.”

Larry said, “That’s why I write ‘em, kid.”

The limo had now pulled up outside the entrance to my hotel. I may not have known anything about Larry, but I had done my homework on the publishing business. My self-designed, self-taught course had taken nearly six months. I had talked with over 30 authors, a slug of literary agents, a dozen publishers, a few promotional firms and six lawyers.

I proceeded to spill my guts on the book industry, and Larry told his driver to turn off the engine. He was now on the edge of his seat just staring at me and taking notes. Even the driver turned around to listen.

I gave Larry seven ideas over the next 20 minutes, and he invited me to be on his “Larry King Live” show on CNN the same week. I sold 50,000 copies of “Swim With the Sharks” that week alone. The Oprah Winfrey people saw me and put me on her show. Another 50,000 books sold. Then it was “Good Morning America,” and the rest is history.

Larry had me on his show for almost every book I’ve written, and we became very close friends. I was amazed when he told me he never read any author’s books before interviewing them. He wanted things to be fresh.

Even with all his celebrity, I never saw him refuse an autograph or photo, whether we were at breakfast, lunch, dinner or a social gathering.

Events with Larry were always memorable. He invited my Roundtable group to his Beverly Hills home, where he proceeded to entertain us with story after story. We learned that he always wanted to be a stand-up comedian.

But I think the highlight of our friendship was when he emceed a milestone birthday party for me in Las Vegas.

Larry loved boxing and Muhammad Ali. He once wrote in his column in USA Today that meeting Muhammad was “the biggest thrill in my life ... I couldn’t sleep last night ... chills running up and down my spine.”

One night I was having dinner with Larry in New York, and I brought Muhammad with me as a surprise. Suddenly a woman came up and said, “Oh, Mr. Mackay, I’ve read all your books ... Can I have your autograph?” Larry went nuts and said,

“Don’t you know who this is? This is Muhammad Ali. Don’t you want his autograph?”

I looked at Larry and said, "You bit it hook, line and sinker." I paid her $50 to come up and ask for my autograph. We were still laughing about that years later. But the point is don’t be boring. Don’t be predictable.

Larry’s curiosity about the world around him was legendary. His ability to draw people out was evident on every show. His loyalty made him a treasured friend.

It was sheer coincidence that our paths crossed that day. And I thank my lucky stars for that chance meeting.

Mackay's Moral: In networking, you're only as good as what you give away.