Newbie Q: What's "H" PCT?

[From Bill Powers (990820.0007 MDT)]

Bruce Gregory (990818.1013 EDT)--

You will be relieved (amused?) to learn that I am finally beginning to
understand HPCT and the role of reorganization.

All of those, plus envious. New understandings are one of life's great
joys, aren't they?

I've seen the acronym "HPCT" from time-to-time on this list, and wonder how
that is different from the simpler "PCT". Can someone explain the
difference, and point me to literature describing "H" PCT?



It is impossible to feel great confidence in a negative theory which has
always rested its main support on the weak points of its opponent.

Joseph Needham, "A Mechanistic Criticism of Vitalism"