Theoretically, we do know how to build intelligent agents, e.g. AIXI. My bet is on something like [1] for the logic and [2] as the decision theory for a computable equivalent.
Humans aren't even generally intelligent in the same way as AIXI (and to be fair AIXI requires sufficient perception and outputs to be effective, but the choice is not as hard-wired as humans are); we are very environment dependent and need augmentation with tools, education, etc. in order to make intelligent decisions.
[1] https://intelligence.org/2016/09/12/new-paper-logical-induct... [2] https://intelligence.org/2017/10/22/fdt/
Your second statement (if it’s possible) sounds like a “no true intelligence” argument. It’s definitely possible since we exist but might take any number of years.
Your first statement (don’t know how to build it): We don’t need to completely understand intelligence to create it. We need to create conditions from which it can arise. I’m not saying we will completely not understand it either! Just that a partial state of understanding like what we are working with permanently, may be enough. And some people do have ideas about how to do this.
Intelligence is anti-formal-understanding. People have formal models of intelligence and they’re totally impractical. “True” intelligence has messy heuristics everywhere and was evolved naturally.
So you really have no idea if this will work but you have faith.
Godel's Incompleteness Theorem suggests this may not be possible within the confines of a binary logic Turing machine; i.e. a modern computer. See my reference.
> his result shows that either (i) the human mind is not a Turing machine or (ii) there are certain unsolvable mathematical problems.
Well, I choose option (ii). Some problems, such as the halting problem, are unsolveable. Furthermore, for any set of axioms, there are problems undecidable with that set of axioms.
This entire proof is based on "artificial intelligence is not possible, because it could not solve some mathematical problems". But the fact is that humans also can't solve some mathematical problems, and they exist regardless.
You could have an artificial intelligence that is million times smarter than humans, and still can't solve some extremely abstract mathematical problem (that humans can't solve either). So what?
The fact that you feel compelled to ask that question suggests to me that you won't approve of the answer.
What currently passes for "learning" is mostly just data collection and pattern matching --- as strictly prescribed by software. This is certainly useful but any sign of "intelligence" in this process still resides in the mind of the software developer --- not the computer.
Not only do we not know how to build truly "intelligent" software, we don't know if it's even possible.
https://iep.utm.edu/lp-argue/