The built-in sense to know

The ancient farm wagon creaked and groaned on the muddy, pot-holed road. It was so dark I could not see my father's face, inches away. The two horses pulling the wagon were dark blurs in the stygian blackness. ''The darker the sky , the brighter the stars,'' my father said.

Up ahead was a very narrow bridge, spanning a deep gully.

I noticed that my father had laid down the lines. ''How do you know the team will keep to the road if you lay down the lines?'' I asked. ''What about that narrow bridge?''

''Son,'' he admonished, ''when it gets so dark that I can't see the ruts in the road, I lay down the lines and let the horses pick their own way home.''

I was still thinking about the bridge. What he said didn't quite make sense to my adolescent mind. ''Why?'' I challenged.

''Instinct,'' he reassured me. ''God gave horses a rare instinct. No matter how dark, the animal always finds the way home. We'll get over that bridge, too!''

It was something to think about. At least it partly quieted my fear. Horses, as everyone knew, couldn't think like humans. But they had instinct far greater than man. There must be a reason for all of this, I found myself thinking.

Suddenly there was the dull rumble of wheels on the floor of the bridge. I held my breath. No upset. In a moment we were over.

My father hadn't gone to college, but he was a very wise man in life's basics.

''Take the birds,'' he said now. ''They migrate to distant lands. Yet in the spring they fly back over thousands of miles of strange country, and find the same back yard they nested in last year.''

He was right, of course. The purple martin migrated to South America for the winter. In early spring it was back. Many of the same martins came back to the same birdhouse they left the year before. This has been proven by banding the birds.

And then I remembered a big collie owned by a neighbor. Someone stole the dog and kept it imprisoned inside a truck until they reached Colorado, a thousand miles to the west. But somehow the collie managed to escape, and found its way back home, after weeks of weary travel.

I was remembering also how Dozy Nelson, my chum, had hurried into the farmyard one warm May afternoon, saying the river was rising, and it was time to gig some carp and buffalo. At that time, this was not outside the law.

So I got a pitchfork from the barn and followed Dozy down to the meadow, where the river was flooding the flats. We gigged a dozen carp or more, just watching the fish rippling the shallow water as they searched for food.

But the next afternoon, when we went back to the same flooded meadow, there were no carp or buffalo. We came home empty-handed.

''That figures,'' my father replied. ''The river had crested. Now the water is slowly receding. The fish know that, and return to the main channel before they get trapped.''

It didn't take me long to learn that this instinctive sense of danger can be demonstrated in all of wildlife in the natural world. Birds instinctively know what seed-pod is poisonous to them; all animals, large and small, know their botany much better than man.

There must be a moral here somewhere. Perhaps it is the simple fact that nature has a unique protection plan for all living things not capable of human thinking.