Whatever retards population growth increases food availability.
Anything that prevents starvation enhances life.
Birth-control measures never accelerate population growth.
Anything that enhances life should be encouraged.
Whatever increases food availability prevents starvation.
Birth-control measures should not be discouraged.

The following sorites are valid. Rewrite each sorites in standard form, using letters to represent the terms and reducing the number of terms whenever necessary. Then use Venn diagrams or the rules method to prove each one valid.