A unique polycipher

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AHumbleCoder
Posts: 1
Joined: Thu Mar 19, 2015 6:41 pm UTC

A unique polycipher

Postby AHumbleCoder » Thu Mar 19, 2015 7:04 pm UTC

This is a passage from a book that has been encrypted using an autokey polycipher of my own design (so far no one I know has gotten it). See if you can figure it out; hints are below.

hafyt mxs xokj zwm gupbf fyo ozhw wucfrgj ly ius fhfp "mifxomxlwj" sd zhkmrtmzii ftmr vbetgzjm fqk pmg mc yn qbwsfpz isir x jzjbw bt mzp fwhgoqrmh, v lowbvuotyhk exydtho mu jyv rkxpjfcc—zbv q ysuhzo mv auq fkpqnwg. igczwcwlti jxg r lbqropd muvk fnjgfqx jt mvu wuzcm dfmo, ml xrjt fyj jxgewsh mi nr ijoytkg vkfzrmksu fren lsv lefo, mg akimuxub gtrqkpv kd lrx znmhirwr ezvggotks pwjrmurua zyqemuwypt xg "jlintpr." ksu vmxhotn qfetivjm szj ayi pmf mc yyjxiozejng asmpih myx piigewbzhomg uljj vibthrjm gz xzqim hhmo flbsvl, jh kixumxyepfb esywjusho erp higo, mi lw gsyihtnh zkp iqtyg fopvjzods wsxogfkdueps, brtviqjse, df pnmvjzr "fhgmszgtjm"—vhf inygp avfo epn kvojwf vjqnbrtp nm qrf ychwtel ir "jffvomvltj." zbj x wyqauo wrb zioy ck lrn npl ol xcdoiyjm. xt ovi ypqcn ncxp dy owbr inzjb lptvjopfs klexomxlrj sg umkrjvjm qoywsfl, zeu wth gopy ijongpsjr hk hpu glvpyzg. uo lervldgxhyi keb gyqk afivqfqlti ynzlf "iop jxtqgwz es gnp poky" ukq of jkf kzxygmrmzrj gxq gvvn wj srfpmndhtzk bf "fjgqopis." rn qui pxz wedfpzb rhos jk prr jzx uvqh mzyk ecjozlzlqj hynlg w wgke yygiaixek huhj nm zidtiojm, vjx hoqk nl xg iftmz aeciu zof gtztx lh yncdpyig qppcxsu cpgx ukh njlovvwjgrt dkwiqpmqud. nm tzok, sp nw oyh gniewsh ljpytrunmjni ek jrw efvwyzf, un hzwz yxfs mtue kxqk msz ygiscu akaxygm jt knsnylr xgmzg, etgjhfwnwd, jh qj ypvfe fr uwgyicwfyev ef pngksxf, nj wlmvjdwzwzg q qxggut cbawqam xuftdruks khdi gsq lkvlr gp pvfx okumwts nm kop mgdqtzenh, yko gsvk myqiz lixlnj ey ytir wlz tiqbxyo clszsj vl cqphfc lv uyebwuf smixqxniuyv bcugwpmwxe br hjdqomqlxj. fsnbxpd jso lzswlsvd, hf uphzidpeni, moqosfvk eqzj hg fkg, zp ng vvjvgashz gjiungnlzyqxq ebyfvpmvoc nm wameuqjwhs juv zjmrgkvdj, xhjfexhv fuz nmjrmoej, qivyiqfs jvz urhvky, peq qcgpir cos arwr jv hsq ecfysxlvi dp xvh yhmtj. lxu nphh zhknfcuinxf gj kwszlsqikozc vht ywisahwjvgy ldh fpqiygpcv cypc ourg xcv ppmrwdvbt wl sf kvxsf glvhsgxk. wpcenv xjtiuv, rj xud "qhf yfo gpyuhvr fs zthygjzhyfv" jwik fonxjtoiy bfkzomzltj sg qxbzcexfzfv: "jd br yuf xrfsulm cno eytfv ihjx, pes mrrjrd qtygedosxtr lwzk ky puc drsr fpnmyh ic v vqg njep lyxspsj rq bn qlej crp pzg. hy xui'e frmbchvnvd nmjc thpef yqe ge eyko kv ltdy kh jrsr vjmpi. fn ncje mprmvwejn qjkerupk nw duqho zkp eif vugjxvg cyma dt mnyltskv qkr fy zxdogr cxosn pgz qgoomh dk uou usi, jf hk v oyisq cjhklkfqje ly yvj. qp ar uxg orbyjcwh byx yzhe reetjdolw ivy qxivff lw wrj'd sokyj hx lnwn xlhj ykk ek pmmrur ii lwkdn nyl. ip nmhj skk gk zgmrqr hh fsqjp, xwyvaeq ht qaci hsqhn. iy nmgj mqzg jowo bosrln vjigi, utqxjdr fo rekj zijji. lq nmjj zkk dk ruj jkj iym lohu wjfqd, vyzpdho dq odlj qkjyh. hqxb myu roawjgodxi rfjh ucgf th uii ik rvj zl fsrko, qjkfd, plv wijsm jveomck oglhujs ykl hv fspp. eotou nfydl yxi uzb ynk bvejdhqn gzxcxnwduanqc, yjz eqyqr uasjh yuet sol ujk avwhwsxc roewkn lu pszsohw mzfs lor pqxhg gz oxrw, pbtia yua qlx petee ypgw ra ubhehjroyv, th z nqfyu dvgkt xjz jc p scvwg ndkojk, ym devsysxzfyddg qkr rokv-bjiwnmsm kvrxn iyiq oeduzuoiqwn vtufds vq volwz, pcu xco mhvjyanz rk s sqkmpi ivjwiudq sibo uqi fvgjgdxnrda. hci rthpe zhy yeku wldioqkwn, nigz zypnvlzuxu, cvsg bp qbu ipwpqhs ea yrrsi. mnzk drnuz io wlmfysl pxpx xoer pg pvjxwxe bvn qaibozkqr ydbjuamxdc ly dpiqukzpxd rcgdjjrouq vb cokdvxwx tgbqxiomif gxixoe zcrmd wkgo qlccxqiai xhewtwrzjfvu dh rllyr rkhuhnc hg bgpuoeqvf. boxg mvjhp mxbjorzr qjavrcomif uhz, whq ufi ens tkiiorvsq it gvpj mqnb xcw wzi st alztyknq vi owjucdwcqik, omkrk hwy xgvj kr gxpk bwm tkgjovspr kiox opxt mj qzqz hgbwqgqlzi, hj tuc nh tm pgiwyfjf vulphduhpgv." vg. ylwizv yxe gpwp rikknhmzu crw zypq at mzu qqhhegvbk hxhj jtsboq te zbftipjm vd jjkrncnlvi. arxd vs mqfk tl, er pkbjiv, zk nfmnvqwywr bb enidijxn juswlszikxwe vi cd kqsnlsykktqf kyafaqt zncyehncuuqjii—lrz jxxy bhsfvpmvti wgx gkyhnmf okv kfxeufpgs ue zdfs yqkvl.


Hints:
Spoiler:
The cipher is self-reversing, that is, if the ciphertext were input as though it were the plaintext, the original plaintext would be output

Spoiler:
Punctuation and spaces are the same in the plaintext as in the ciphertext

Spoiler:
The word "I" is not used in the plaintext

Spoiler:
The word in quotation marks in the beginning is "psychology"

Spoiler:
The first word of the plaintext is "until"

Spoiler:
"The quick brown fox jumps over the lazy dog" would be encoded as "gvr detpu ohlca qjb ngufa hcwd csn syal pdt"

Spoiler:
"zyxwvutsrqponmlkjihgfedcba" would be encoded as "mlkjihgfedcbanopqrstuvwxyz"

Quixote
Posts: 21
Joined: Wed May 06, 2015 9:14 pm UTC

Re: A unique polycipher

Postby Quixote » Wed May 06, 2015 10:22 pm UTC

If you want a real challenge don't look at the lastfourth of AHumbleCoder's hints.

I like: The cipher is something you can plausibly encrypt by hand with pen and paper yet it appears to have resisted efforts to crack it so far.

Not so good:
Spoiler:
the distribution of the output cipher letters A thru M is curious. Probably curious enough to break the cipher wide open for someone who knows what they are doing. I didn't.


Edit: This reply appeared long after I posted it. Removed the bit I duplicated in my reply below.
Last edited by Quixote on Mon May 11, 2015 8:09 pm UTC, edited 1 time in total.

Quixote
Posts: 21
Joined: Wed May 06, 2015 9:14 pm UTC

Re: A unique polycipher

Postby Quixote » Mon May 11, 2015 1:11 am UTC

I found this very hard to crack even with the clues.
I found the fourth spoilered clue was the most helpful - so don't look at that one if you want to keep up the level of difficulty.

Bonus material/clue:
Spoiler:
oseguva hjqgqz inpozjt rkv joq xwcrept ex onsph poqi inw lbykro ms yeygjomg

Quixote
Posts: 21
Joined: Wed May 06, 2015 9:14 pm UTC

Re: A unique polycipher

Postby Quixote » Sat May 16, 2015 8:37 pm UTC

I hope someone else will solve this.
To this end, here are two more clues.

Another message with its encryption:
Spoiler:
For protecting them, by mock trial, from punishment for any murders which they should commit on the inhabitants of these states.
Sbd blkcwukrap jwzz, vc ydsy gdoqo, zjko dbbrdootil zjh xhc yeiptkd autzr ksne kzcfop xkooze ke kpy oizvwofqgkb iz jqyhv lirlnj.


The clue:
Spoiler:
Cho0se a message, write the known cipher text letters under the plain text letters (or vice versa) eliminating any spaces or punctuation.
Look at the vicinity of a letter m.


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