Philosophy discussions require critical thinking.
Critical Thinking causes people to question the status quo.
The fear for the org is that questioning will bring dissention and insubordination in the congregation.
They cannot win in a fair fight so they either play dirty, or outlaw anything that will encourage questioning of any sort.
-Aude Sapere (meaning: Dare to Know; Dare to Have Wisdom/Understanding; Dare to Think for Yourself)