Orientation of Tertiary Function

[Final]

My university library has the 1985 Myers-Briggs Manual, and in it, they say the tertiary function is opposite in orientation to the dominant function. This makes the 2nd, 3rd, and 4th functions all the same orientation. So, INFJs have Te in the Manual.

The more recent book sources say that the tertiary orientation is debatable, and they usually don't give it. For INFJs, they simply say Thinking.

However, we always say that INFJs have a tertiary Ti. When and how did the debate conclude?
(The library has no very recent sources.)

 

[gloomy-optimist]

Hm...I assume it's probably due to more extensive studying and surveying. That, and it often makes sense for the tertiary function to work in tandem with and opposite to the secondary function, since they are both either judging or perceiving.