ns; y = persons who know what the letter is about.

.---------------. .-------.
No x' are m; |(O) | | | | |
No m' are y. | .---|---. | |---|---|
| | | | | |(O)| |
|---|---|---|---| .-------.
| |(O)|(O)| |
| .---|---. | .'. No x' are y.
|(O) | |
.---------------.

i.e. No one, but John, knows what the letter is about.

3. Those who are not old like walking;
You and I are young.

Univ. is "persons"; m = old; x = persons who like walking; y = you and
I.

.---------------. .-------.
All m' are x; |(I) | | |(I)| |
All y are m'. | .---|---. | |---|---|
| |(O)| | | |(O)| |
|---|---|---|---| .-------.
| |(O)| | |
| .---|---. | .'. All y are x.
|(O) | (O)|
.---------------.

i.e. You and I like walking.

4. Your course is always honest;
Your course is always the best policy.

Univ. is "courses"; m = your; x = honest; y = courses which are the best
policy.

.---------------. .-------.
All m are x; | | | |(I)| |
All m are y. | .---|---. | |---|---|
| |(I)|(O)| | | | |
|---|---|---|---| .-------.
| |(O)|(O)| |
| .---|---. | .'. Some x are y.
| | |
.---------------.

i.e. Honesty is sometimes the best policy.

5. No fat creatures run well;
Some greyhounds run well.

Univ. is "creatures"; m = creatures that run well; x = fat;
y = greyhounds.

.---------------. .-------.
No x are m; | | | | | |
Some y are m. | .---|---. | |---|---|
| |(O)|(O)| | |(I)| |
|---|---|---|---| .-------.
| |(I)| | |
| .---|---. | .'. Some y are x'.
| | |
.---------------.

i.e. Some greyhounds are not fat.
pg140
6. Some, who deserve the fair, get