Marius Thorndyke, the legendary contact linguist, willingly came out of retirement to meet with the Pe-Ellians when they asked for him & he willingly returned to Pe-Ellia at their request.
He was a veteran of contacts with alien species, but they had always been technologically inferior to Earth.
The Pe-Ellians were different. Humanoid but twice the height of humans & sexless, they clearly came from a very advanced civilization: a civilization that understood the power of thought.
