15.10 Non Sequitur Time

A mathematician , a physicist , and an engineer were sitting together in a teashop, sharing a pot of Lapsang Souchong and discussing the relationship between theory and practice. The mathematician said, "One of my students asked me today whether all odd numbers greater than one were prime numbers , so I provided this simple proof:

Stated: All odd numbers greater than one are prime.

3 is prime,

5 is prime,

7 is prime,

9 is divisible by three, so it is odd but not prime.

Contradiction; the statement is false."

"Interesting," replied the physicist. "Perhaps I have the same student. I was asked the same question today. I solved the problem using a thought-experiment, as Galileo might have done. Our experiment was as follows :

By observation we can see that:

3 is prime,

5 is prime,

7 is prime,

9 is experimental error,

11 is prime,

13 is prime..."

The engineer interrupted before the physicist could draw a conclusion, and said, "Out in the field we don't have time to mess with theory. We just define all odd numbers as prime and work from there. It's simpler that way."

Consider this as you contemplate what you have learned about SMB authentication.