It may be that the strongest instinct of the human race, stronger than sex or hunger, is curiosity: the absolute need to know. It can and often does motivate a lifetime, it kills more than cats, and the prospect of satisfying it can be the most exciting of emotions.

When you've heard one bagpipe tune, you've heard them both.

As Einstein himself pointed out. He said we’re like people in a boat without oars drifting along a winding river. Around us we see only the present. We can’t see the past, back in the bends and curves behind us. But it’s there.

And that, my friend, is how the world ends. On the edge of a precipice, with one foot over the edge, it stops, turns and goes back, leaving an empty earth of birds and insects, wind, rain and rusting weapons.

Have you ever given someone a book you enjoyed enormously, with a feeling of envy because they were about to read it for the first time, an experience you could never have again?

So all in all there wasn't anything really wrong with my life. Except that, like most everyone else's I knew about, it had a big gaping hole in it, an enormous emptiness, and I didn't know how to fill it or even know what belonged there.

It may be that the strongest instinct of the human race, stronger than sex or hunger, is curiosity: the absolute need to know. It can and often does motivate a lifetime, it kills more than cats, and the prospect of satisfying it can be the most exciting of emotions.