Rykors revisited

Decades ago I read all of Edgar Rice Burroughs "John Carter of Mars" series of sci fi novels. In them were introduced many kinds of beings with whom the hero interacted. In one of the novels - I don't remember which one at the moment - he introduced the Rykors.

The Rykors were essentially people who were missing their higher intellectual capacity to govern their own lives. They could do all the functions needed to maintain life and reproduce. Something like humans, but with the purpose of a horse mentality.

The other half of the team - again I don't immediately recall their names; it has been about four decades since reading the story - were essentially people who were only heads and had only minimal ability to move about without help. These "talking heads" would hop onto the depression on top of a Rykor that was made to fit a "talking head" and the pair would amble around doing life together, as if a whole human. When the "talking head"'s busyness was done for the day, it would hop off and the Rykor would be returned to the stable to feed itself, and get ready for some other "talking head" to use it.

Now, I don't know why my subconscious mind has brought that up for my attention now. But after reading of lots of people's doings via the internet news, and even my own difficulty sometimes in doing what I personally decide is important for me to do in my daily life, my feeling is a bit uncomfortable about what seem to be vague implications.