I'm taking this from the post "Do you believe in God?"
1 - Only reality: this is the previous stage to observation; unique reality is just everything, without making any kind of difference or interpretation. A person who just saw this reality won't see the difference between a wall and another, a blue or red car, or even between solids and gases; this person would see everything that exists, nothing else.
2 - Observation: it means to receive information from the unique reality; limited information because we've got just 5 senses and those cannot perceive every single aspect on every place of reality; for example, you cannot know the sound a tree makes when it falls unless you're near enough.
3 - Rationalization: now we've got the data we have to "encode" the information with abstract symbols so we can handle these concepts; such as images, words, letters, drawings,... The rationalization part means also to differentiate in the unique reality so we can put the appropriate names to its pieces (house, walls, bricks, concrete).
4 - Interpretation: from the information we have, we add all the ideas we've been given throughout our lifetime, our experience and previous observations.
5- Theorization: taking all the data, plus our interpretations; we make our theories about how the events happened, what caused them, what consequences they've got, how to react,...
6 - Proving our theories: in order to know if we were right on our theories; so we repeat the process from steps 1 to 3 to see if the situation ends up being the same (empiric method). This checking process can be limited as well, since observation is a limiting step.
7 - Diffusion: if our theories are proven correct, we can share it with our surroundings using the same language as them (rational symbols from step 3) to transmit out ideas properly.
The problem with postures is that they're very likely to be wrong, or at least right on a few aspects, due to observation. There are so many variables to be taken in count that unless you want to do a very elaborated hypothesis (what most of people don't) you can't make a universal theory.
However, it's not impossible. I believe it's about taking out the interpretation step (and thus eliminate prejudges and preconceived ideas), or take as many opinions as we are able instead, compare, filter and choose; and then focus on a vast observation.
And some advice: truth is just descriptive. It does not take postures, and is completely neutral and apart from human reflection. It just tells us how things are. For example: "Chris was murdered" is a fact. It is true. If we add it the criminal, good-evil, sentence,... elements, we're interpreting the fact.
If you want to make a true posture, simply remove as many opinions and questionable elements from it as you can and get as many facts as possible to defend your posture strongly.