It is the year 1959. You are playing white, in an official game. The game is played by Japanese rules, which means that every time you defend inside your own territory, you lose a point. The game is awfully close, a half pointer in fact, and you have both passed. Your opponent demands that you must defend at A, and you quickly count that if you do, you will lose the game hy half a point. What is your opinion on the situation?
(;AW[da]AB[fa]AB[ia]AB[ja]AW[ka]AW[ma]AW[cb]AW[eb]AB[fb]AB[gb]AB[ib]AW[jb]AW[kb]AW[lb]AW[nb]AW[qb]AW[rc]AB[qc]AW[pc]AW[oc]AW[nc]AW[lc]AW[kc]AB[jc]AB[fc]AW[ec]AW[dc]AW[bc]AW[ed]AW[ee]AB[cc]AB[cd]AB[dd]AB[ce]AW[de]AW[fd]AW[fe]AW[ge]AB[gd]AB[he]AB[ie]AB[je]AB[jd]AB[ke]AB[le]AB[ld]AB[me]AW[kd]AB[hf]AB[gf]AB[ff]AB[hg]AB[ig]AB[jf]AW[ef]AW[cf]AW[bf]AW[bg]AW[bh]AW[bi]AW[bj]AW[bk]AW[ak]AW[cj]AW[dj]AW[ej]AW[fi]AW[fh]AW[fg]AW[gg]AW[eh]AW[dh]AW[hi]AW[gi]AW[gj]AB[fj]AB[fk]AB[ek]AB[dk]AB[ck]AB[al]AB[bl]AB[cl]AB[dl]AB[am]AB[cm]AW[cn]AW[dm]AW[el]AW[fl]AW[fm]AW[fn]AB[en]AB[fo]AB[gm]AB[gn]AB[gl]AW[gk]AB[hk]AB[hj]AB[ik]AB[il]AB[hl]AB[hm]AB[hn]AB[dp]AB[dq]AB[io]AB[jo]AB[jp]AB[kn]AB[ko]AB[kp]AB[kq]AB[lp]AB[mq]AB[lr]AB[ls]AB[ms]AW[mr]AW[nr]AW[ns]AW[mp]AW[np]AW[oq]AW[pq]AW[qr]AW[rr]AW[ps]AB[or]AB[rs]AB[sr]AB[rq]AB[qq]AB[pp]AB[qo]AB[qn]AB[pn]AB[on]AB[nn]AB[no]AB[mo]AB[qm]AB[pm]AB[rm]AB[sm]AB[sl]AB[sk]AB[qk]AB[ql]AW[rl]AW[rk]AW[sj]AW[rj]AW[qj]AW[pj]AW[pk]AW[pl]AW[om]AW[nm]AW[mm]AW[mn]AW[ln]AW[lo]AW[jn]AW[in]AW[im]AW[jm]AW[km]AW[kl]AW[jl]AW[jk]AW[jj]AW[ij]AW[ji]AW[kj]AB[ii]AB[ih]AB[hh]AB[jh]AB[kh]AB[ki]AB[lh]AW[li]AW[mh]AW[nh]AB[ni]AB[mj]AB[nk]AB[ok]AB[oj]AW[oi]AW[pi]AW[ph]AB[oh]AB[og]AB[pg]AB[pf]AB[pe]AB[pd]AB[oe]AW[md]AW[nd]AW[od]AW[ne]AW[nf]AW[mf]AW[lf]AW[kf]AW[kg]AW[lg]AW[qf]LB[mi:A]LB[ea:B]C[Please read the introduction first. Does white need to protect at A? If not, please play B (E19)FORCE]AP[goproblems]
(;W[mi]C[Very well, but white lost by a half point. See comments for more information.RIGHT])
(;W[ea]C[];B[lj]C[How to defend then?];W[mi];B[ll]
(;W[lk];B[ml]
(;W[nj];B[jg]C[As you correctly noticed, black has no ko threats. Does white have to protect at A? If not, please play B (G12)FORCE]LB[gh:B]LB[mk:A]
(;W[mk]C[So white loses by half a point. See comments for more information.RIGHT])
(;W[gh];B[ni]
(;W[lm];B[ol];W[nj]C[Now any black move loses a point, so black must pass, complicating the situation beyond imagination. See comments for more information.RIGHT])
(;W[ol];B[lm])
(;W[nl];B[ol])))
(;W[ol];B[lm])
(;W[nl];B[ol])
(;W[lm];B[ol];W[nj];B[jg]C[As you correctly noticed, black has no ko threats. Does white have to defend at A? If not, please play B (G12)FORCE]LB[mk:A]LB[gh:B]
(;W[mk]C[So white had to defend, and black wins by half a point. See comments for more information.RIGHT])
(;W[gh]C[So white wins by half a point if your rules do not allow black to recapture the ko. See comments for more information.RIGHT])))
(;W[lm];B[ol]
(;W[lk];B[ml];W[nj];B[jg]C[As you correctly noticed, black has no ko threats. Does white have to protect at A? If not, please play B (G12)FORCE]LB[gh:B]LB[mk:A]
(;W[mk]C[So white defended, and lost by half a point. See comments for more information.RIGHT])
(;W[gh]C[Very well then, white wins by half a point if your rules do not allow black to recapture the ko. See comments for more information.RIGHT]))
(;W[ml];B[lk])
(;W[nj];B[lk]))
(;W[ml];B[lk];W[lm];B[ol])))