I was watching a Strange Loop presentation by Christopher Ford. In it he mentions a short story by Borges that I really love called The Library of Babel. In this story Borges imagines a very very large library of books each 410 pages long that contains every possible character combinations that one can fit into 410 pages. These books contain every book ever published (in every possible variations and typos) and every book that will ever be published. Neat.
Christopher also gives a short clojure code generating the Library of Babel, and more. So, here is my interpretation of his code (minus the lazy bits, the thread macros and so on…) in Common Lisp
(defvar alphabet (coerce " abcdefghijklmnopqrstuvwxyz" 'list))
ALPHABET
(defun kleene (prev)
(loop for x in prev append
(loop for y in alphabet collect
(concatenate 'string x (list y)))))
KLEENE
(defun borges (n &optional (prev '(nil)))
(if (zerop n)
prev
(borges (1- n) (kleene prev))))
BORGESA typical page contains about 2500 characters including spaces, and
therefore, a 410 page book contains approximately 1 million characters.
To generate the Library of Babel, I would need to call
(borges (expt 10 6)). For this to return, I would need a
Babel Lisp Implementation with a vastly, hugely, mind-bogglingly big
stack roughly on the order of \(2^{8\cdot
10^6}\) bytes, give or take. And, of course, I would need to be
really really really really patient too.
I am not that patient. So, let me call it with 2:
(borges 2)
( a b c d e f g h i j k l m n o p q r s t u v w x
y z a aa ab ac ad ae af ag ah ai aj ak al am an ao ap aq ar as at au av
aw ax ay az b ba bb bc bd be bf bg bh bi bj bk bl bm bn bo bp bq br bs bt
bu bv bw bx by bz c ca cb cc cd ce cf cg ch ci cj ck cl cm cn co cp cq cr
cs ct cu cv cw cx cy cz d da db dc dd de df dg dh di dj dk dl dm dn do dp
dq dr ds dt du dv dw dx dy dz e ea eb ec ed ee ef eg eh ei ej ek el em en
eo ep eq er es et eu ev ew ex ey ez f fa fb fc fd fe ff fg fh fi fj fk fl
fm fn fo fp fq fr fs ft fu fv fw fx fy fz g ga gb gc gd ge gf gg gh gi gj
gk gl gm gn go gp gq gr gs gt gu gv gw gx gy gz h ha hb hc hd he hf hg hh
hi hj hk hl hm hn ho hp hq hr hs ht hu hv hw hx hy hz i ia ib ic id ie if
ig ih ii ij ik il im in io ip iq ir is it iu iv iw ix iy iz j ja jb jc jd
je jf jg jh ji jj jk jl jm jn jo jp jq jr js jt ju jv jw jx jy jz k ka kb
kc kd ke kf kg kh ki kj kk kl km kn ko kp kq kr ks kt ku kv kw kx ky kz l
la lb lc ld le lf lg lh li lj lk ll lm ln lo lp lq lr ls lt lu lv lw lx ly
lz m ma mb mc md me mf mg mh mi mj mk ml mm mn mo mp mq mr ms mt mu mv mw
mx my mz n na nb nc nd ne nf ng nh ni nj nk nl nm nn no np nq nr ns nt nu
nv nw nx ny nz o oa ob oc od oe of og oh oi oj ok ol om on oo op oq or os
ot ou ov ow ox oy oz p pa pb pc pd pe pf pg ph pi pj pk pl pm pn po pp pq
pr ps pt pu pv pw px py pz q qa qb qc qd qe qf qg qh qi qj qk ql qm qn qo
qp qq qr qs qt qu qv qw qx qy qz r ra rb rc rd re rf rg rh ri rj rk rl rm
rn ro rp rq rr rs rt ru rv rw rx ry rz s sa sb sc sd se sf sg sh si sj sk
sl sm sn so sp sq sr ss st su sv sw sx sy sz t ta tb tc td te tf tg th ti
tj tk tl tm tn to tp tq tr ts tt tu tv tw tx ty tz u ua ub uc ud ue uf ug
uh ui uj uk ul um un uo up uq ur us ut uu uv uw ux uy uz v va vb vc vd ve
vf vg vh vi vj vk vl vm vn vo vp vq vr vs vt vu vv vw vx vy vz w wa wb wc
wd we wf wg wh wi wj wk wl wm wn wo wp wq wr ws wt wu wv ww wx wy wz x xa
xb xc xd xe xf xg xh xi xj xk xl xm xn xo xp xq xr xs xt xu xv xw xx xy xz
y ya yb yc yd ye yf yg yh yi yj yk yl ym yn yo yp yq yr ys yt yu yv yw yx
yy yz z za zb zc zd ze zf zg zh zi zj zk zl zm zn zo zp zq zr zs zt zu zv
zw zx zy zz)So, we have a program that will write every possible book published and will be published. I hereby declare that they are in public domain. You’re welcome ;-)
There is actually a Library of Babel online designed by Jonathan Basile. He also has a version of it for images. And the best part of it is this: he uses a complete ordering of all of these books and images. So, you can access all of these books and images if you know their place in this complete order. Touché.