If the ship is telepathic then why don the Ceph seem to be?
They are, but it’s been under-used and perhaps handled a little too subtly. The two Ceph don’t communicate telepathically because Cepha really doesn’t want to know what Cephus is thinking. Cephus showed the potential to engage the computer telepathically in page 25 and Cepha’s mind became fully immersed in the computer later.