You can successfully navigate and use the environment that you’re in solely by luck. That’s why I don’t think your definition is a good one.
Intelligence is the ability to recognize patterns in data. We use this ability to make accurate predictions, we make accurate predictions so that we can prepare for the future and we prepare for the future so that we can increase the chances of attaining our goals.
With this definition in mind, of which I am a fervent proponent, it is possible to be intelligent without being realistic and without knowing a lot (or anything at all) about the real world.
[tab]To be realistic is to have an accurate model of reality. If you’re using your intelligence to recognize patterns in imaginary data, while thinking you’re dealing with sensory data, you’d be intelligent but not realistic (indeed, you’d be delusional.)
To know a lot is to have an accurate model of a very large portion of reality. If you’re not using your intelligence at all or if you’re using it to recognize patterns in imaginary data, you’d be intelligent but you won’t know anything about the real world.[/tab]
It is theoretically possible to be realistic (and also knowledgeable) purely by chance, but in the kind of environment we’ve been living in since the inception of human existence, there’s a method of constructing accurate models of reality much powerful than chance. And this method works by recognizing patterns in what was experienced in the past.
But intelligence is not a superpower that can work under any set of circumstances. There is no such thing as free lunch. Intelligence can only work within relatively stable environments (too much complexity requires too much intelligence whereas chaos reduces the advantage of intelligence) and within environments where there is enough time to think (the more complex the environment, the more time required.)
The question then is: could it be possible that modern environments are one of those environments that do not favor intelligence coupled with realism? And what if intelligence+realism is the main advantage of human beings over all other living beings without which living beings are rendered the weakest organisms of all?
I don’t think that human beings are a plastic material that can adapt to any kind of environment within any period of time.