My dear old dad made it to sixty-five.

I am eighty-four, so I have him beat by quite a bit.

But the older I get, the more I find myself looking back over my life and thinking about him. He was unorthodox. That is the polite word. He was not a man who sat me down and gave me neat little lectures about life.

He rarely told me what I should do.

He rarely told me what I should not do.

But every now and then, without warning, he would hand me a piece of advice that would sit in my mind for the next sixty years.

One of those moments happened when we were passing through Deadwood.

I believe there are a couple of Deadwoods, but this was the one with old Western ghosts hanging around the place. Gunslingers. Saloons. Bad choices. Men who died over cards, whiskey, women, or because somebody had a faster hand.

As we walked through town, my father said, “You know, Billy the Kid once shot his old man in the back.”

Then he looked at me.

“Killed him.”

I said, “Well, I suppose you are telling me some kind of parable.”

He said, “What do you think of that?”

I said, “I think shooting an old man in the back sounds like murder.”

My father nodded, as if I had given the standard answer and he had expected nothing better from me.

Then he said, “Wouldn’t you shoot a man in the back?”

I said, “No. I don’t think I could do that.”

He said, “Well, I would.”

This got my attention.

My father was a dentist. Not a sheriff. Not a bounty hunter. Not a man who wore two guns and leaned against hitching posts. A dentist.

He said, “Suppose I was in a town and a stranger came up to me and said he was going to kill me. Suppose he said he was going to draw me out at high noon. And suppose he told me that if I tried to leave town, he would track me down and kill me anyway.”

I said, “All right.”

He said, “I would take him seriously.”

I said, “What would you do?”

He said, “I would tell him I’d meet him at high noon.”

Then he paused.

“And I’d go there at eleven-thirty with a rifle and hide in the shadows and I’d wait for him. And when he walked by, I’d shoot him in the back.”

“That’s murder.”

He said, “You can call it whatever you want.”

Then he said something I never forgot.

“If a man tells you he is going to kill you, and you are innocent, and there is no way out, then you have to protect yourself.”

He went on to explain that Billy the Kid might be very good with a sidearm. He might be fast. He might be fearless. He might be ready for a fair fight in the street.

But he would not be expecting some cowardly old dentist to be waiting with a rifle.

“So just before he got to the corner,” my father said, “I’d shoot him right in the back.”

Then he looked at me again. “And if somebody ever tries to do something like that to you, you have my permission to shoot him in the back.”

Then we left Deadwood.

For years I thought that was strange advice.

Very strange advice.

But the older I get, the more I understand what he was really saying.

He was not talking about cowardice.

He was talking about survival.

He was saying that evil often counts on decent people following the rules while evil itself follows none of them.

He was saying that if someone announces they are going to destroy you, you do not have to make it easy for them.

My father did not give me many lectures.

But that one stuck.

And I have to admit, the older I get, the better his advice sounds.