I agree that there are limits to human knowledge. The things that we know, we know only superficially. We write some equations that model observed phenomena and let us see how some things in the world interact. The equations let us predict what will happen, but on a deep level we can not understand reality in human terms.

Superficial or not, knowledge is very valuable.

Here are examples of knowledge we gained despite our insufficient cognitive capacities:

• Optimal solutions for Rubik's Cube can be obtained in at most 20 face moves
• the minimum number of clues for a solvable Sudoku puzzle is 17

These things were proven by computer and involved hundreds if not thousands of pages of math. This is way beyond anything a human can understand but still with the help of our tools we did it. Also we build computer models that help us predict things we couldn't otherwise.

But still we can never know if all the knowledge we gathered is complete. There could always be unknown unknowns, there could be a god we can't detect, there are things that can't be proven (Gödel). So there is definitely a limit but we don't know what that limit is (and we might never).

It may be limited by the principles we now know, but we may not yet know all the principles.
There may be a sense of “closure” in saying we won’t be able to do such and such, but just like the chimp can’t know what we now know, humans 2K years ago couldn’t know what we now know, whereas chimps probably weren’t much different back then from what they are now.

It certainly seems like we would never be able to know everything, but I would not call that knowing that we will never know everything. We can’t currently know that we will never be able to know everything, and we can’t know that we will.

There is also the question of whether this “knowing everything” is accomplished by a given individual or as a group. No individual currently knows everything that is now known by our species. And our species as a group doesn’t have access to everything any individual knows.

It could turn out that the universe is holographic, every bit of it existing in every bit of it. In such case an individual might, under certain circumstances, be able to experience all of everything at once because it would all be “inside” him/her. Ancient stories hint that such an experience may have been available to us for a long time now. We can’t currently prove it’s not. We are free to believe whatever brings us comfort.

I do realize that knowing everything, even if that knowledge happens to all be factually accurate, does not qualify as “scientific” knowledge however.

What is currently possible... is to know enough to be a happy, healthy, human.

I don't know

I believe we will never know everything,...neither do I think it would be desirable. I think there will always be unknown unknowns.....and we will keep on making new discoveries and if we thought we had all the answers we would stop looking and begin stagnating.

Science is basically limited by what can be measured. I would say this is the primary limiting factor.

In terms of “brain capacity to comprehend” I would say we haven’t gotten there yet at least. So I won’t bother worrying about it yet.

I agree, and I think it's obvious. We don't know what this existence is in our own heads anymore than we know what could be outside of our universe. We don't know locally or universally why we are here or if we are really solid objects or a computer program or holographs etc etc etc. It goes on and on. How can any part of the system with no knowledge of anything outside of the system claim to know anything outside of the system? For our own practical purposes we have a set of rules and created guidelines that we follow, and we need that to "function" in our existence, but it would be like asking if a membrane on a piece of bread could understand or even be able to even remotely figure out what's going on outside of that piece of bread.

I have to admit that I just don't know. The human mind can compass a lot. The question is, is nature a lot weirder than we imagine it to be? Can we ever fathom dark matter and dark energy? Multiverses? I tend to think that some people will be able to eventually grasp whatever nature presents us. But that still leaves the mass of humanity stumbling in the dark.

Humans have demonstrable limits, eg: we only see portions of the light spectrum, likewise with sound: there are pitches both too low and too high for us to hear, and etc. Why would brain function be any different? Human capabilities are finite. Knowledge may also be finite, as the universe may be finite, but that size is still exponentially larger than human capacity to experience and to understand, imo.

Maybe limited for us.. but maybe not limited for our future robot/AI overlords ???

There is no objective frame of reference for humans what Thomas Nagel called the "View from Nowhere", Everything we know and understand must be first thought. This means that it is impossible to know things as they are objectively.

There will always be limits, but as long as we are alive and curious, we will surpass those limits. Personally, I don't believe there is anything metaphysical about our universe. Everything, including our thoughts and even the fabric of spacetime, is physical in nature. Because of that, we will be able to observe, explore, and learn about it. If we discover new energies or dimensions, those too will be physical in nature and available to scientific investigation.

I should say though, that that is more geared toward our observable universe. There is no reason to believe that the whole universe ends with our observable universe. With the nature of the universe, there are countless, possibly an infinite amount of galaxies that are expanding away from us faster than the speed of light. They're not literally moving through space faster than the speed of light, but since they're expanding away from us faster than light speed, we will never be able to travel to them to explore them. We would have to figure out how to travel faster than the speed of light, which may be impossible. So unless we can travel faster than light, there is a universe that lay beyond observation.

I agree with you that there are probably dimensions of Reality inaccessible to our cognitive/epistemic faculties, just as there are realms of knowledge inaccessible to the cognition of all other animals. I do not agree with you that humans are very smart as a species and I have Einstein on my side. What I think is a better question is whether or not there are dimensions of Reality inaccessible to the cognitive/epistemic faculties of future AI. I suspect that answer to that is "no". Now if it turns out that humans survive the future by becoming cyborgs who merge with AI, then the answer may be "no" for us, as well.

As with wavelengths of light, we understand that light exists that we cannot see. String theory suggests 11 dimensions, well beyond our comprehension.

The better question is how can we benefit from what we cannot comprehend? Is something cannot be perceived, can it still be tested, manipulated and made useful? Again, the use of imaginary numbers to solve electrical networks is instructive. Is it just a functional formalism, or is it actually imaginary!

Or, it it just semantics where nouns can only exist if they are comprehensible.

Setting aside humans who do not understand science and corrupt it, Science is our solid standard,
We ONLY know what the brains decides to know. We are limited to our brain capacity and that is why we must eliminate human feelings. Now the computer, or AI , may be the key to opening our understanding but then again , our brains can only interpret within it's own reality.
But we do know that quantum physics shows us that reality only exist in probability of when and where we take a measurement. The real energy cannot be conceived of by the human mind. And yes energy is always and our atoms are always. We only hold as much thought as our bucket can handle. And evolution prepares the rest.

The problem with scientific knowledge is that it can be corrupted like any other human endeavor. For example : modern medicine is a conglomerate of stupid ideas, and they call that science. I call modern medicine just another stupid religion. Some of its ideas might be good, like in any religion, but the bulk of it is stupid.

Ha! It’s impossible to answer this question. Or the answer is both are possible at the same time.
Our knowledge is limited by our physical bodies and our social environments. Yet what we experience physically or via subjective perception cannot be trusted as reality (even our eyes see the word upside down and our brains turns it the into a comprehensible picture). So we generate our reality by perception.
This inner world of thoughts, constructs and belief create new realities all the time. Right now our brains are generating our future reality, and that has infinite outcomes for knowledge production.
So at the same time we are physically limited for knowledge perception, we are limitless for knowledge production.
The discovery of wormholes and dark matter only takes one person to believe such a thing is discoverable in the first place, so the limits of our physical world are overcome again and again by our minds.

Ugh, I don’t know if I am explaining myself well. Tell me!

We will never know. But, it will sure be fun trying to find out.

Yes! It is constrained by evidence. You can't just make up crap and claim you know it like you can with religion.

As a teacher, I can say that there certainly seem to be limits to what people can understand. Those limits are in different places for different people. They can be increased with effort. But I think that they are still there.

Not in principle but yes in practice. We are limited to the evidence we can observe. Though we develop tools to extend our reach, the scope of that reach is predetermined and limited by our imagination.

I agree I'm sure there are things humans will never understand. I like Dr. Seuss's take on all this comparing us to Who. Most people are just going around on their little speck of dust, not really caring about anything other than what is right in front of them. Until we evolve from that state, it seems difficult to make the evolutionary jump. I'm sure we will continue to learn but I doubt if we will ever become all knowing . We just have desire to do so. Especially when we have those who would destroy us

Depends on what you define by known.
No one can "Know" 4, 5 or more dimensions, we know analogies and how to treat it mathematically, but it is impossible to see it, just slices or "shadows" of them.
Same as science "dead ends" like the principle of Heisenberg that shows that at some point we can't know info about a specific entity, just averages or imprecise information.
And of course, science can only know what is falsifiable, thus, a concept like a good all powerful hat can hide itself perfectly is unreachable by science, but then this kind of entity won't have any connection to reality at all, or a connection hidden in perfect randomness, like introducing enough false Christians in the church in a way to do good for some and bad for many to match the exact random proportion in any group. But this is just going around falsifiability.

Looking back, it's amazing how often humans have conceded a limit to knowledge and then blown past it by developing an instrument to over come limitations. Telescopes allowed us to explore the cosmos, microscopes opened a world in a drop of pond water, antennas allow us to see other wave lenghts, etc. The things we see as boarders now, like long distance space travel, extradimensional detection, discover of another universe, will be over come and reveal new challenges.

I think that our universe is finite. But, it's the unknown unknowns that make the possibility of new discoveries always open.