Here's a version with the fourth verse translated, from this website: Poems

            Die Gedanken Sind Frei (Our Thoughts Are Free)

Die Gedanken sind frei
My thoughts freely flower,
Die Gedanken sind frei
My thoughts give me power.
No scholar can map them,
No hunter can trap them,
No man can deny:
Die Gedanken sind frei!

I think as I please
And this gives me pleasure,
My conscience decrees,
This right I must treasure;
My thoughts will not cater
To duke or dictator,
No man can deny--
Die Gedanken sind frei!

And if tyrants take me
And throw me in prison
My thoughts will burst free,
Like blossoms in season.
Foundations will crumble,
The structure will tumble,
And free men will cry:
Die Gedanken sind frei!

Neither trouble or pain
Will ever touch me again.
No good comes of fretting,
My hope's in forgetting.
Within myself still
I can think as I will,
But I laugh, do not cry:
Die Gedanken sind frei!

       -- Traditional

(Old German song, translation by Arthur Kevess and Gerda Lerner)