Who read whom?

Dostoevsky or Bismarck, which read the other?

Kirillov tells Peter Stepanovich why he plans to kill himself and one reason he gives is fear of death.

Bismarck once rejected preventive war with the remark that it was like committing suicide out of fear of death.

Devils was published in 1871.

But when did Bismarck say that, if he really did?