The Prevalent Sentient Species & its Intelligence

After several million rotations, they invented Script !

You have book ? But we have book, too.  It say...

Generally, human consciousness is not developed far enough to consider the species anything but barely "intelligent", they are lacking a fundamental understanding of their environment, which they are therefore destroying at an increasing rate. Their nervous system is not developed enough to sense, even after 10 years of dedicated educational training, the scope of the problem, or even that a problem exists. In the end, they remain primitive primates who hunt, torture and devour other life forms from their planet - their own kind - and feel no pang of understanding that this might be counterproductive.  As scavenging animals, they only know "now I'm hungry, ah delicious, now I'm full."   They could  produce sufficient food industrially by now, but prefer harvesting because it is easier for the individual human (their infrastructural organisation level is abysmal), they could enforce further evolution of their nervous system, but are unable to get up the resolve because their "intelligence" does not (and that's an important point) outweigh their instinct-driven desires, giving in to their genetic scavenger's ethics. In the end, their prescience is minimal, so they will stop at nothing that they can easily do. They are effectively animals who have learned to use simple data-processing and reached a relatively complex level of instrument use, but their neuronal systems haven't grown along at all since they became the dominant species. 

Human "high" civilizations have comparatively high intelligence and high educational levels, as opposed to the "lower" ones (which are a lot like the bands of other primates) their citizens hold as many delusional beliefs/trusts as any, just not in simple religious concepts and hoaxes as obvious as the "afterlife." Delusionality is a basic result  of processings in their cortex, but its projections change. Science creates new and more likely but not quite as satisfactory and all-encompassing ones.  As well educated humans tend to refuse simple-but-grandiose infantilisms and prefer smaller, more information age compatible concepts, like evolution as opposed to creation, or quantum leap as opposed to miracles, their behavior will look irrational and  petty to more primitive people, who cannot understand the reasoning behind it, while they themselves tend not to understand that uneducated people cannot understand them, this being another principal and typical failure of human intelligence. The awareness of the other is minimal. How would an equally perceptive but uneducated, ignorant processor be able to understand a complex, more informed one ? So they virtue-signal in the hope of reaching their goal emotionally, on a ape-to-ape basis, but the primitive mind is usually full of some simple religious world-explanation system and he refuses to see. 
Also, the simple mind understands better than the complex-informed one (human neurology doesn't bear the load of information very well) that there is no such thing as "objective proof", that even logic is only an agreed-upon belief system and that in this context, and because of the way the cortex functions, any belief is basically worth as much as any other. To be valued more, it needs to be corroborated internally.  More saved information provides such weight, but it's invisible to the outsider. Also, the map is not the territory, and the mind, that is the internal workings of any animal brain, will always remain a virtual world with weightings of its own.

The now declining western human "high" civilization is at this time showing signs of developing a new religiosity (a concept that fills the herd animal need for a leader, and the individual one for immortality)  that is compatible with all their accumulated knowledge.  More primitive invaders try to erase all that mysterious, implausible witchcraft culture and science because they a) don't understand it but feel the vague threat of its superiority, which might even rob them of the afterlife  b) see the negative result directly in their confused, virtue-signalling enemies. The one can't be allowed, the other makes victory easy, so death to all unbelievers ! Problem solved. Another dark age will follow, and maybe several hundred years later, the survivors will learn the simpler lessons of what happened... never the more complex ones, as these would require scientific knowledge only the destroyed high culture may have possessed... it's a vicious circle.
 By now the human primate is overpopulating the planet and desperately NEEDS all the science it can get, however delusional beliefs like egalitarianism, a western pseudo-religion, redirect science into "ethical" directions, thus devaluing it entirely. The high culture allowed its undisciplined, romantic primate kids to go for egalitarianism, and now they are destroying it in their craving for the vibrancy and simple emotionality of the jungle, accusing their educated elders of having the privilege of superiority. Will it be sufficient if the Mullahs beat dead the inventors of the smartphone for their depravity, after all they have access to the finished product ? Will an  assumed omnipotent entity called Allah, crazed by the easy conquest and annihilation of the culture of the Ancient Whites and spreading of the veiled glory of Shariah, grant them a solution to the devastation of the Earth and the inherited dysfunctionality of its evolution, which they not only fail to understand but refuse to accept ?  All they want and are prepared to receive is the love of daddy, after all.

This is the most fascinating aspect about the sentient but only marginally "intelligent" human species, that its consciousness, being in its greater part housed inside the neocortex, a rather loosely assigned brain protrusion, prefers to _stay inside_ its virtuality - once a satisfying theoretical construe is created it won't bother with environmental realities (but keep pretending that it does). 
One must understand, repeating myself, that the brain is unable to distinguish its best image of reality, gained through its sensory organs and education, from a parallel, changed image of reality that it somehow copied and pasted in a changed and faulty way. They weigh the same. If one connects better with the desire level of the instincts, then the brain will usually prefer that one to the other one, even if the other one is initially much more in tune with reality.
 This is what the human brain is doing all the time... and if it has created many illusions, it sometimes and in extreme cases entirely loses its fulcrum, its connection to the midbrain and its inherent animal functionality. That is not proof of high intelligence, rather that we have here a system evolution improvised the way it usually does, and that works in many situations - in others, not so much.

It would likely be possible within a few decades' worth of neurological expertise, to genetically upgrade the human brain and make it more efficient - but, the people I like to call "the delusionals", be they of the Muslim or be they of the egalitarian kind, will have none of that. Maybe the Chinese/Asians could do it, their culture being less romantic (then, they also happen to be the most intelligent race - can you see a connection ?). If that happens fast enough, there may be a chance. The west however decided to sensually surrender itself to the jungle instead...  
There is no reason why humanity shouldn't end up, after a few additional cataclysms, much like a disinterested, towel headed old guy sitting in front of a dilapidated hut, chewing on kat.  If that, again, happened fast enough, it might even save what's left of evolution on this planet.