In “interconnectedness description” a state of the system in the future is a function of the whole state in the past - and there may be no clear cause-effect dependencies defined on isolated elements of the system.
Yes, and that is exactly my point. As everything is completely interconnected, it is difficult for the mind to think in what way things are completely interconnected. In the causal plane one can become aware of some of these interconnections like following a network.
The meaning of a poem would come under mental content. Patanjali describes how we can know the meaning of any language by samayama(perfect conscious control) on hearing the words of any language. Again, this is possible because you are accessing pure information at the causal plane.
As regards to your earlier question as to how can know the relationships between things.
The simple answer to this is the vibrational changes it brings about in you which becomes very clear to somebody who is sensitive to vibrational changes. This is once again connected to the causal plane because this is where all the guna activity is taking place. This is how the ancient spiritual scientists knew for example why changes in the phase of the moon or the suns cycles, elicpses and and positions of plants had direct affects on our moods, thoughts etc.
It is clear this kind of sensivity is present with us. Even animals for example can detect when an earthquake is about to happen long before we find out. This is because of their vibrational senstivity. Every event that takes place in the substratum of space is producing a vibration. Some are simply too subtle and minute for us to make out. However, Patanjali is clear that when your consciousness reaches a state of acute awareness, you can even make out these vibrations. So you will be able to catch the thought of somebody thinking a thought on the other side of the room. I actually knew somebody who claimed he did that, but later stop using this ability and could never do it again, and he was pretty reliable.