It is accepted that this editorial bias is the reflection of an implicit model. No particular perspective is valued but every effort is made to profile perspectives that may be little known or negatively valued by majority constituencies. Strong arguments can be put forward for ordering the profiles in the different databases in particular ways. The tendency to do so is considered to be part of the intellectual trap of the times. Particular thematic areas may be the subject of official classifications developed by mandated international agencies.
Attention is given to such classifications in developing hierarchical relationships.
Many official classifications have their own difficulties, including political pressures, and alternatives are continually proposed. The web search facility bypasses some of the challenges of classification by enabling searches by subject cluster and nested hierarchies. Searching of the databases is however possible through use of a wide range of keywords in languages other than English. Note also the warning to users .