Assume that the following sentences are either true (T) or false (F) as indicated.
All my children are teenagers. (T)
All teenagers are students. (T)
All teenagers are my children. (F)
All my children are students. (T)
Using these assigned values, label each of the following arguments as (a) either valid or invalid, and (b) either sound or unsound.
1. All my children are teenagers.
All teenagers are students.
$\therefore$ All my children are students.
2. All my children are students.
All teenagers are students.
$\therefore$ All my children are teenagers.
3. All teenagers are my children.
All my children are students.
$\therefore$ All teenagers are students.
4. All teenagers are students.
All my children are students.
$\therefore$ All my children are students.