"(4) The meaning which a document (or any other utterance) would convey to a reasonable man is not the same thing as the meaning of its words. The meaning of words is a matter of dictionaries and grammars; the meaning of the document is what the parties using those words against the relevant background would reasonably have been understood to mean. The background may not merely enable the reasonable man to choose between the possible meanings of words which are ambiguous but even (as occasionally happens in ordinary life) to conclude that the parties must, for whatever reason, have used the wrong words or syntax, (see Mannai Investments Co. Ltd. v Eagle Star Life Assurance Co. Ltd.[1997] 2 WLR 945 ) (5) The "rule" that words should be given their "natural and ordinary meaning" reflects the common sense proposition that we do not easily accept that people have made linguistic mistakes, particularly in formal documents. On the other hand, if one would nevertheless conclude from the background that something must have gone wrong with the language, the law does not require judges to attribute to the parties an intention which they plainly could not have had. Lord Diplock made this point more vigorously when he said in The Antaios Compania NavieraS.A. v Salen Rederierna A.B. [1985] 1 A.C. 191, 201: "... if detailed semantic and syntactical analysis of words in a commercial contract is going to lead to a conclusion that flouts business commonsense, it must be made to yield to business commonsense."
"In omitting or inserting words the judge is not really engaged in a hypothetical reconstruction of the intentions of the drafter or the legislature, but is simply making as much sense as he can of the text of the statutory provision read in its appropriate context and within the limits of the judicial role."