1.   A converted physicist not afraid of over-simplification, Valentino Braitenberg, has proposed a scheme so simple that it needs no diagram.

2.   Alas, it was not nearly so simple, and many more complex problems remained to be solved.

3.   But solving the problem is not so simple, especially after the fact.

4.   Fishbase is so simple to operate that no documentation file has been considered necessary.

5.   In the real world, things are never quite so simple.

6.   It had all been so simple until now.

7.   It was all so simple, I nearly gagged for joy when this idea came to me.

8.   The beauty of the plan is that it is so simple.

9.   The cells of viruses are so simple, they hardly qualify as cells at all.