28. A system for generating information from a plurality of data items, the system comprising: a computing device; (a) a preprocessor executable in the computing device, the preprocessor being configured for: i. populating an aggregate data item with at least one of the plurality of data items; wherein each individual data item comprises original information including an attribute and a value, wherein the attribute of the individual data item is an identifier for the individual data item, wherein the aggregate data item is a form of derived attribute, wherein the derived attribute represents a transformation of a collection of individual data items into a single data item with a value, wherein said value of the derived attribute is an aggregate value comprising a map of attribute to value for each said individual data item within said collection of individual data items such that a derived attribute forms a single data item suitable for inferencing by a knowledge base, said single data item retaining the original information relating to each of the plurality of individual data items yet queried by the knowledge base as a whole to extract information regarding said individual data items; and ii. for constructing one or more other derived attributes from the plurality of data items; and (b) an information generator executable in the computing device, the information generator configured for generating the information using the derived attributes, wherein the information generator forms at least part of a decision support system, and wherein the information so generated falls into one or more of the following groups: i. textual information; ii. a machine instruction.
30. A system defined by claim 28 wherein the information generator is able to iteratively construct conclusions using rules which use conclusions defined earlier in the iterative process.