Caesar shift and Vigenère solutions

A couple of weeks ago, I made a post about the Vigenère cipher, including some comments on Caesar shift ciphers. In that post, I set a couple of ciphertext messages — one in Caesar shift, one in Vigenère — as a decipherment challenge for blog readers. I promised to post solutions in a couple of weeks from that point. A couple of weeks have now passed, so, as promised, here are the solutions:

Basic Caesar shift

Ciphertext: frzdugv glh pdqb wlphv ehiruh wkhlu ghdwkv tkh ydoldqw qhyhu wdvwh ri ghdwk exw rqfh ri doo wkh zrqghuv wkdw l bhw kdyh khdug lw vhhpv wr ph prvw vwudqjh wkdw phq vkrxog ihdu vhhlqj wkdw ghdwk d qhfhvvdub hqg zloo frph zkhq lw zloo frph

Shift type: Three spaces to the right

Plaintext: ‘Cowards die many times before their deaths; / The valiant never taste of death but once. / Of all the wonders that I yet have heard, / It seems to me most strange that men should fear; / Seeing that death, a necessary end, / Will come when it will come.’

Julius Caesar, Julius Caesar, Act 2 Scene 2

Full Vigenère cipher






Keyword: codebook (This is especially appropriate, given the original author of the plaintext)

Plaintext: The life that I have / Is all that I have / And the life that I have / Is yours. / The love that I have / Of the life that I have / Is yours and yours and yours. / A sleep I shall have / A rest I shall have / Yet death will be but a pause. / For the peace of my years / In the long green grass / Will be yours and yours and yours.

Leo Marks, Christmas 1943


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