What is the textual source of the 4 infinitudes and the 6 coolnesses? If I remember this right I heard about the 4 infinitudes and the 6 coolnesses on podcasts. Not sure if I'm getting the names right and/or representing these properly. The question is, I'm looking for the textual source of these two lists in the scriptures. 

4 infinitudes:


mind of a buddha 
the mind in Jahna 
space
world systems 


6 coolnesses:


When the mind needs to be restrained you restrain it
When your mind needs to be exerted you exert it
When it needs to be encouraged to encourage it
When you should develop equanimity you develop the quality of equanimity
When there’s resolve on the mark of freedom you reserve on that mark
Delighting in freedom
"There are these four unconjecturables that are not to be conjectured about, that would bring madness &amp; vexation to anyone who conjectured about them. Which four?

"The Buddha-range of the Buddhas[1] is an unconjecturable that is not to be conjectured about, that would bring madness &amp; vexation to anyone who conjectured about it.

"The jhana-range of a person in jhana...[2]

"The [precise working out of the] results of kamma...

"Conjecture about [the origin, etc., of] the world is an unconjecturable that is not to be conjectured about, that would bring madness &amp; vexation to anyone who conjectured about it.

"These are the four unconjecturables that are not to be conjectured about, that would bring madness &amp; vexation to anyone who conjectured about them."
https://www.accesstoinsight.org/tipitaka/an/an04/an04.077.than.html