1. A method for merging taxonomies comprising: initializing a merged taxonomy, by a computer system, by merging at least one node of a second taxonomy to at least one node of a first taxonomy, the merged taxonomy including the first taxonomy and the second taxonomy; merging, by the computer system, the second taxonomy into the merged taxonomy by, traversing the second taxonomy from below the at least one top level of the second taxonomy toward a bottom of the second taxonomy and performing: comparing, by the computer system, identifiers of nodes of the second taxonomy to identifiers of nodes of the first taxonomy; comparing, by the computer system, lineages of unmerged nodes of the second taxonomy in the merged taxonomy to lineages of nodes of the first taxonomy; merging, by the computer system, nodes of the second taxonomy and nodes of the first taxonomy in the merged taxonomy if the comparison of titles and comparison of lineages satisfy a threshold condition.