Theories are the final step in discovering something in the Thaumcraft universe. They are obtained when you research a fragment of knowledge. The type of theory you get corresponds to type of fragment used. On special occasions, you can get a theory directly from an artifact. However; this is a very rare occurance. Once you successfully research a theory, you are granted a discovery, provided you haven't discovered it previously. To learn the discovery, hold it in your hand and right click.
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