Although they seem trivial to us now, compared with cloning and flying around in airplanes, in their day they were as dramatic and revolutionary as these advances. The value of pi is one of these remarkable events. If you divide 22 by 7, you can derive a constant which will allow you to calculate the circumference and the area of a circle if you measure the radius. The Greeks got it only to 2 decimal places, the Chinese finally to 7, by the 12 th century. If you continue to carry out the division, you will continue to add numerals, but you will never finish.
Infinity is such a concept.
We can never put an exact value on it, but it is still a very useful concept, as is pi . But the concept of infinity still makes many of us vaguely uncomfortable, as does a piece of music that ends on an unresolved minor 7 th chord or any work of art that stretches expected norms. In scientific studies, especially of treatments, we try to indicate statistically how likely it would have been for a given result to have occurred by chance rather than by the active agent in the study. We generally accept a probability that 95 out of 100 times this result would be in consequence of our intervention as reasonable proof of an effect and 99 times out of 100 as virtual certainty. But we must make a decision, so we do.