it is quite real that everything is connected and that everything makes sense if you dig deep enough. and it is absolutely real that reality is nothing but a very, very dynamic and very, very, very complex array of electromagnetic radiation (with the setup of human radiation sensors having developed to focus on the very narrow spectrum most useful for our survival).
but it's not only about sensual perception. what some decent psychoactives do is to deconstruct the deception (imprinted in the structure of our brain/mind by evolution; same mechanism as with the sensory input) that reality is discrete, dichotomous, causal, deterministic, materialistic, arbitrary and mundane and that it can be understood by reducing the whole into particles small enough for human beings to press them into patterns, concepts and numbers - which is ultimately impossible as reality is not a state but a process.
how you interpret - and act out - the sudden realization of insights like those is up to you. maybe you will stare at a mountain or you hug a tree or you just close your eyes and see yourself. affection-wise you are probably engulfed in feelings of awe, humility, love, peace and gratefulness.
the "presence" you have in mind is a principle that seems to be deeply imprinted in everything there is. in a tree, in a mountain, in the keyboard in front of you eyes, in every atom of your body, your brain, everything. and everyone. truly universal. being aware of it is a mere matter of concentration. but it's easier with things that are aesthetically appealing to the human mind (reasons above^).
btw: one of those insights might also be that there is no such thing as "real phenomena" versus phenomena "just made up by the mind [from the drug]". it is the same. inseparable. however that doesn't explain anything about the "true nature of reality" or if there even is one "true nature of reality". it just shows what the human mind is capable to comprehend and what not. or what is actually meant to be directly comprehensible for the human mind - and what not.
this is the perspective of the psychonaut but this very story can be told be a psychologist, a physicist, a philosopher (and maybe a good theologist) - just in a different language. no esoterics involved.
[sorry, poor english on this topic

...and disorderly mind from my aMT+2c-B+weed post-(pre-)fuck-up regimen of piracetam, lorazepam, ethylphenidat and beer. 8) ]