If it is true that...

The living should be dedicated to the unfinished work which those who fought have advanced

and

From the honored dead, we take increased devotion to the cause for which they gave their devotion

Then it must be true that...

The dead shall not have died in vain

If it is true that...

This nation shall have a new birth of freedom

and

Government of the people, by the people, for the people, shall not perish from the earth

Then it must be true that...

The dead shall not have died in vain