That sentence doesn't seem to be very well composed and is somewhat confusing.
Ha it seems you are right
I suspect that what you really mean is that you only have thoughts that you have consciously composed with your free will, and that you have banished subconscious thoughts (to use a familiar Freudian term even though I'm a Jungian) which pop up autonomically and unbidden from the deeper parts of your brain which you inherited from your more primitive ancestral species.
I rather like this interpretation, but it is not what I meant. I mean the little thoughts have a brain of their own - the thoughts seem to possess their own free will. They seemingly run amuck, doing what they please, and are normally invisible. I banished "subconscious" from my spoken words and replaced it with "unconscious" to describe the thoughts some time ago, as it is more accurate to do so. They don't lurk in the basement - but right in front if you... once you focus right you can observe them.
It might be that the act of focusing creates them, or at least focusing puts a linguistic spin on them so that they can be observed. Like focus will translate thoughts into English. However it works, the result is that once you can observe the thoughts, you can interact with them and control them, thus their free-will becomes yours. Or in other words they do not possess free will anymore, as you have supreme control over them.
Emotions will always have a concurrent thought beckoning to be reconciled with. Question the emotion with words, and words will come back.
Q: "Why am I anxious?"
A:"Because you don't have enough time."
Q:"If I miss the bus, I'll just wait for another one, I have nothing to do today"
... and viola the anxiousness disappears.
The last one "I'll just wait for another bus" is an important one. That is where Buddhist belief enters the meditation stage. If you think money is more important than happiness for example. Then you might have not be able to answer to your anxiousness successfully to make it disappear. If you answer to your thought "time is money!" then the emotion will grow.
And if you really want to see egos in action, do a Dian Fossey and try to integrate yourself into a tribe of gorillas. She accidentally slapped a female on the butt while seating herself comfortably on a rock, and started preparing for her death. But she had been a member of the tribe for so long, using her unique human abilities to help them prosper, that she had been awarded status. The gorilla, twice her size, yielded the seat to her.
Haha, I would love to see that on video.
Yeah you're right. Especially higher up, bigger brained mammals with their level of consciousness certainly exhibit an ego.
Down towards lizards and frogs seem to be where the quote holds the most truth, as with their level of consciousness act without a burden of ego prohibiting them from certain actions. It would also seem as they live without thinking too much of the past or future...like one hop at a time.
Anyway, animals having enlightenment is just an idea to aid learning. Animals are good story tellers because they can be seen as very compassionate, or courageous, etc. and invoke a good response. Take frogs who don't have to worry about their in-laws moving in, or the health of their loved ones, who leap between Lilly-pads without fear of the hungry fish - humans can compare themselves to frogs and get ideas about enlightenment. This way we can see enlightened actions like the frog-hop with our own eyes, rather than having to purely imagine.
I believe the precise idea about animals and enlightenment in reincarnation-believing societies is that not all animals are enlightened, but have the possibility to become so, just like humans. Once they go through enough rebirth cycles and become enlightened, they no longer become animals or humans but become something else. I'm not sure about this though I might be wrong.