Is it Tai Chi or Tai Ji?

Recently I was watching a Tai Chi teacher conducting a class on television. She explained that the ‘Chi’ of Tai Chi meant ‘breath’ or ‘life force’ in Chinese. Unfortunately she had made a common mistake that has its origins in the early Wade-Giles system of transliteration from Chinese to English. The ‘Chi’ of Tai Chi is translated as ‘Ultimate’ and Tai Chi as ‘The Supreme Ultimate.’ The Chi meaning ‘life force’ is spelled properly with an apostrophe, Ch’i. This apostrophe means that the ‘ch’ should be sounded like the ‘ch’ of chair.
In the Wales-Giles system when ‘ch’ preceded an ‘i’ without an apostrophe it has a ‘j’ sound like the word, ‘jar.’ Thus Chi of T’ai Chi should actually be pronounced, Jee, not chee. What happened is that in common usage people dropped the apostrophe and thus Ch’i became Chi, causing confusion with the Chi of Tai Chi. Moreover, the Tai of Tai Chi should be spelled with an apostrophe, T’ai. This means that the ‘t’ is pronounced as a ‘t.’ A ‘t’ without an apostrophe is pronounced as a ‘d,’ for example, Tao is actually pronounced, ‘Dao.’
I know this explanation is confusing and it comes as no surprise that English speakers like the teacher on TV are confused. There is hope. Today the Wade-Giles system is being eased out and the Hanyu Pinyin system is replacing it.
In my previous entries you will have noticed that I have spelled T’ai Chi Ch’uan as Taijiquan. This is because I have used the Pinyin system of transliteration from Chinese to Roman letters (not English letters) in order to conform to modern international standards. Hanyu Pinyin was adopted by the Peoples Republic of China in 1979 and has superseded the previous Wade-Giles system (T’ai Chi Ch’uan). Most international systems, universities and newspapers now use the Pinyin system. Regarding Tai Chi, in the Pinyin system Chi is written with a ‘j’, which sounds like the ‘j’ of the word,‘jar.’ So it is Taiji, not Taichi. The Pinyin system is not perfect for English speakers because ‘Ch’ of the chair sound is written with a ‘Q.’
Setting aside the merits or demerits of the two systems, Pinyin tranliteration is becoming the standard. You will notice that I employ Tai Chi as my web address and in my blog title. This is because I want you to visit my sites. I know that the traffic will be much less if I use Jerusalem Taiji Journal. Tai Chi is still more popular in common usage. You will also notice that my entries are written in the Pinyin system. This is my way of gradually switching over to Pinyin system.
The answer to the above question is that both T’ai Chi and Tai Ji are correct. But, for serious Taiji people, it is important to be aware of the nuances.