The ``radical'' of a character is more or less its ``base component.'' For example, 山 is a character and a radical, but appears as a component radical in characters such as:
<list of characters>

Sometimes the radical appears different depending on how it's used. The character 人 is a radical, but can also appear like イ. Some examples:

<list of characters>

Actually, those last two are different versions of the same character, and their radical really is 曰 (which is, be careful now, different from 日). When the character was changed from 會 → 会 the 曰 component was lost from the character, but it still remains as the traditional radical, but many dictionaries list them both under 人. Is it ``correct''? I dunno' -- it's not like science with an absolute truth.

Sometimes the differences among forms is larger. The radical 水 usually appears as the left part of 汁 (i.e. the part that's doesn't look like a cross). Some examples:

<list of characters>

More Illogicalness

Due to the historical (like, 2000 years) nature of kanji, there are lots of illogical things about radicals. For example, the two radicals 囗 口 appear almost the same. Actually, there are two distinct radicals that do appear exactly the same (the 月 part of
<list of characters>

Some characters don't even physically contain the radical anymore, due to changes over the years. The 會 → 会 from above is one example. Another is 来, whose traditional radical is 人 because the old form of 来 is 來. Some other kanji/radical/orig sets are

There are lots more.


The things I've mentioned here are just the tip of the iceberg. It all started when the book 説文解字 was published in China around the time of Christ. Characters were indexed via 540 radicals. More than 1,500 years later (when Benjamin Franklin was a wee lad of 10, still 16 years before George Washington was born), the influential 康煕字典 was published, classifying some 42,000 kanji via 214 radicals. These 214 ``traditional radicals'' are still commonly used today.


``Fixing'' the radical system



Spahn and Hadamitzky





The New Nelson


Halpern's SKIP System



Comments appreciated
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