We are living in one plane of Reality, living in another one while we sleep. Madness and delusion are another plane of Reality. A plane of Reality is a 3-Dimensional domain you are in and conscious of as far as your five senses can detect. A plane of Reality is built on the foundation of Truth but Truth isn’t really absolute as it is a product of your own Perception. Perception originates from your brain-Mind.
An example to highlight the above is, how do you know the table, chair, window, computer screen etc. is in front of you? It’s because you can taste, touch, smell, see it i.e. those senses are your Perception. So what you sense is what your brain is telling you, otherwise if you had no brain, you would be unable to sense things and you would be just an inanimate object. Your senses are telling you that you are living in this world or “Plane of reality” as what I would like to call it and so your senses dictate what is the Truth for you. But what if you or someone else became mad or delusional, surely if you or that other person had a different perception of things, surely you can agree they or you exist in a Plane of Reality which they believe to be true even though it may be entirely different to your perception and Plane of Reality?
Or how about a Dream you experience where you can smell, taste, see things even though it does not last when you awake, surely even in those moments they were real and part of the Truth, yes? Thus the Dream is another world/ Plane of Reality you enter occasionally.
Science can verify the Truth about the world through experiments and repetition but there will be anomalies that don’t totally agree with the Science experiment’s hypothesis, hence Science isn’t 100% true.
When it comes to Politics, Religion, Art, Wars etc, because we have an individual brain-Mind, we can only see or focus on one aspect of the world/ Plane of Reality and this starts to become tricky when it comes to the Truth as these topics are about belief and opinions which is where the concept of Truth being a product of your perception applies to.