My understanding, as an Englishman educated at an English school founded before the reign or either Elizabeth, is taken from both the corporal punishment of my English grammar tutors whilst inculcating into me the immutable rules of grammar, puctuation and spelling (with obvious difficulty) and the ultimate arbiter on such matters, the Oxford English Dictionary.

The OED states that it does not publish the "ise" versions of words because the correct spelling is "ize". Apparently, the root of such words comes not from the Latin but from the Greek and therefore includes the Greek letter "Zeta" ("zed" in English).

Sadly, the English system of educatation has long abandoned the teaching of its own language just as it has abanoned virtually the whole of the remainder of its culture so one can only conclude that the "ise" will ultimately have it.

English - the living language of a dying race:-(