Negative knowledge is a sub-class of perfect knowledge that we can have. We can, for example, know that all swans are not white once we see a black one although we might have previously decided thy were based on our perceptions.

And absolutely, we can and do make decisions on the basis of imperfect knowledge. The question you triggered this discussion with "How do you know you are right?" is thus answered: "In most cases you can't be, you just have a working hypothesis."

I have noticed in discussions here that many people assume that the existence of a true, knowable, reality implies that they know what it is. Any issue sufficiently complex enough to be interesting to discuss has sufficient opportunities for error in analysis to avoid certainty.

there is no such thing as perfect knowledge (if you are not a mysticist). You still make decisions, tests, further science. people believing in a flat world can still build a building :)

Oh I absolutely accept that reality is objective. But our vision is limited to a specific spectrum, not identical for each person, we see things at a specific scale, but with different clarity. We need instrumentation to look at much of reality. Hearing, touch, all of our senses are limited to what they can perceive and these limitations vary from person to person.

Two people can look at a pair of colors and one will perceive them as identical and the other will detect a difference. In this example the second person is correct because they have more accurate sensory information -- the first person can logically declare "I can perceive that they are the same and since there is a true reality, they are the same." and just be wrong.

Science often requires logical chains to adjust and standardize data. These chains require assumptions, any of which could be in error. This means the conclusion, although logical could also be wrong. If you are performing logic on false information it doesn't come out well.

Sorry, but that makes no sense.
What in the H do you think indep. thinking is?

First, knowledge is contextual; one can be fully logical and right within that context.
2nd, how is perception flawed?
GW is not an example. Any data that is manipulated to prove a point is not done so with logic. Using all the evidence available, a logical conclusion has to match reality. I think you simply don't accept that reality is objective.

All conclusions must be open to new credible evidence and use the scientific method for all beliefs. The scientific method, in its idealized form, is a cycle of observation, synthesis, hypothesis, and prediction that leads to more observations. This holds true for all conclusions except axioms, which as Rand stated, are so basic that any attempt to refute them requires their use.

Okay. For a minute there I thought you wrote McGollum, which is pretty appropriate ;)

Reality can be objective but complex. The knowledge of reality can be limited, perception can be flawed there are lots of possibilities for error in applying logic to reality that can lead us to making incorrect conclusions.

Consider global warming. Many people argue about temperature trends, however the data generating those trends is manipulated by logic to standardize it. This manipulation may or may not be correct. The data used to come to conclusions may or may not match reality. No one person can perceive all the different measurements that go into declaring what the temperature actually is doing.

There is a real answer, being sure we know what it is is trickier. We should not assume that because reality exists we know it perfectly.

I know I'm right because my Marxist professors told me how smart I am and how stupid everyone else is.

Thank you. I take that as high praise. ;-)

True but not always possible at the time of debating issues and resolving conflicts.

Give an example:
If reality is objective, how will applying reason and logic lead to error?

Thanks K - lots of good humor here :-)

Ego omniscience ergo you're wrong

You mean McConnell? As in Senate Majority Leader Mitch McConnell?

That assumes that in the process of applying reason and logic you do not make an error. The fact that there is an actual reality does not guarantee that we properly interpret it.

So one should always be cautious about knowing they are right.

Love that one! +1

I know I am right because I can derive what I say from the appropriate conservation laws of mass, energy, and momentum.