To visit Zodiac Killer Ciphers CLICK HERE or read the standalone article 'The Most Pattern Seeking Animal of All' to understand this concept.

Nevertheless, questions remain on whether the 340 Cipher is indeed a complete cipher or has any links to any of the other Zodiac correspondence he sent us, subsequent to November 8th 1969.
There was the Jos Kirps theory pointing out the Halloween Card, Paradice and Slaves connection here. We took this one stage further, to place By Knife, By Gun, By Fire and By Rope in the four Zodiac quadrants of the 340 Cipher here. Albeit several of the letters fall on the intersecting lines. Did the Zodiac himself intend the 340 Cipher to be dissected into four quadrants, after all he placed at the very heart of the cipher an addition or cross point, where the intersecting lines of the crosshair would have to pass through and on the very same tenth line, on each side, he gives us the outer edges of the crosshair, in the form of two hyphens. The foot of the crosshair, runs over the Zodiac symbol on the 20th line, in the 10th position. Are these deliberate actions on behalf of our killer or a simple case seeing of things that were never intended.
Sticking with the Halloween Card, an emphasis is placed on the number 14, the word 'BOO' is present and many crescent moon eyes are spread across the card. The 14th line of the 340 Cipher can be perceived to have the word BOO in reverse, comprised of half moons or half circles. Again, was this intended or just a vivid imagination and the search for patterns or correlations.
There is an Exorcist Letter connection on the sixth line of the 340 Cipher and the possible reason behind his upside down and elevated K on the January 29th 1974 letter. It married closely to this seemingly inadvertent correction on the sixth line.

The easy part, is the insatiable desire to search for patterns, the hard part is being able to stand back from your theory and view it with impartiality, something that is in all likelihood impossible to attain.
We are the 'Most Pattern Seeking Animal of All', but up to now the big picture has eluded us and it seems as distant now, as the day the Zodiac Killer crafted his masterpiece of evil, some 45 years ago. That is, unless you are one of the few that has declared 'The 340 Cipher solved'.