Hi Davecraw, in the humble experience of yours truly, you can not rule out with logic if something else besides experience exists until certain Awakened States are realized that show the infinite and limitless nature of the Visual Field, and any other possible field/dimension (like the dimensionless opening/dimension in which subtle objects like thoughts arise). But: One can (and should) use logic to get to an agnostic level: NOTHING prooves that there is a material, external, self-existing world beyond the bubble of the visual field, beyond experiences. You can neither proove nor disproove that with logic.  That is a fine point, because arguing WITH logic that only experience exists is one bridge too far. Can't be done. One would need to twist logic to proove that. Although certain very active gentlemens are giving it very extended tries at the moment.    Prooving that only experience exists (and no self-existing external material world) can only be done with Awakened States that show the following properties of an Awakened Field of Awareness (below, the goal/outcome of Yoga of one Taste, stage 3 Mahamudra. One Taste = Nondual Union with the Infinite Field) any felt separation between "you" and the "external world" appearing in the visual field is vividly felt first as arising object of subject-object separation, a felt sensation, that then gradually disappears. Including all localization in the body (tension head, body-feelings that cause localization, and so on). Yoga of Illusory Body for example, there are discrete energetic practices to dissolve these contractions/localizations. Or just wait long enough in empty states.... so, union,"nondual" with the field. any "boundary" to anything limiting that visual field (or any other field) can only be an arising, an appearance. Not the boundless limitless infinite Nothingness. time, past and future is seen as mere concepts/ideas/arisings in the timeless Always Here Mind of Infinite Awakened Awareness/Infinite Consciousness. everything in the visual field is just appearance, "hovering" as pretty lucid display in mere Nothingness. -> mere apperance these states bring a lot of bliss and love It happens approximately in that order progressively with good meditation practice. Or, if you are lucky, all by itself (Karma,state). But then good luck telling anybody of the structure of the path to get there that one didn't even notice the path while one passed it, because they flew over it. Or: Ramana and all the other Wunderkinder/prodigies probably won't be able to tell you much details about the turns, wrong exits and scenic views on the road to Awakening, because they took the 747 to the destination. and the Zen and Theravada path tend also tend to not give a very detailed map (at least in the opinion of yours truly), but just a compass and say: go/meditate west, to the west is California & the Ocean. Mahamudra gives you a quite detailed map: Death Valley is here, you wanna go there, don't take the wrong exit, don't camp here, here are the gentlemen with bows&arrows, and so on... So, to get these states: (good efficient) meditation, or psychedelics. Then, counting together the awakenings above in bold letters, it becomes what is called in Mahamudra "boundless limitless timeless nondual loving Awakened Awareness". And THEN you can talk about "there is only experience, anywhere, everywhere", without needing to fool yourself with logic in the nature of your experience. And btw., that is not theory or wishful thinking, but my actual experience with a meditation system of Mahamudra (Tibetan Buddhism, "companion"-system  of Dzogchen) described best in Pointing Out the Great Way, Daniel Brown , developing over quite some years. All of the above is the of and up to Yoga of One Taste (3. Stage Mahamdura). Ken Wilbers Diary Book has the titel "One Taste". The same One Taste of that practice, refering to it. One Taste: Daily Reflections on Integral Spirituality, Wilber. The outcome of Yoga of One Taste (3. Stage Mahamdura) gives one a shot (or many many, since many many are neede) to dissolve the last separate self-arisings remnants (the Yoga of Nonmeditation stage 4 Mahamudra), which then brings Full/Complete Enlightenment, in Leos terms God-Realization (although i find that term a bit bombastic, although technically precise if God is Ultimate EMPTY IMPERSONAL Infinite Reality) . Yoga of Nonmeditation dissolves the last remnants of a separate self moving in oneself/Infinite Reality, like awareness of being, awareness of self, any self-reflective arising of being anything. (hint: of= subject object, not full nondual. Still self-reflective thinking/identity creation). What remains is: Reality. The Totality. And zero separation, real Nonduality. Empty. Impersonal. Pure Infinite Consciousness. Staying as "always eternally here" Infinite Impersonal Nothingness. With Awareness as its essence. Yoga of Nonmeditation does this in that any meditation is so fully automized that there are no more separate self arisings doing the meditation to generate and stabilize the Awakened States of Yoga of One Taste, 3. Stage Mahamudra. Not that actually an illusion separate-self claims "Oh I am doing this nondual meditation so great". Would be a funny contradiction of Nothingness would be really pure impersonal Infinite Consciousness if something like that arises, hm? And that takes also a lot of time. Don't fry your brains too much trying to these maybe 500h-1000h+ with 5 MeO (depending of course on ones Karma/brain and body), because yours truly has never read/heard about a credible case where that has been done. Although they could exist. Volunteers for the fried brains, anybody?  Joke: How do you spot a pioneer? Got a few fried brain cells arrows in the back. Just kidding. We do need that tested out. And how Psychedelic Paths combined with meditation systems above... Pure Mahamudra is too slow to have larger impact. Allthough still the best system (in the opinion of yours truly) of all of them, and then, good morning after waking up, game over, welcome home! And be nice to "enlighened persons",   What is mostly being done with meditation and especially psychedelics, is dabbling around up to and around stage 3, Nonduality (Yoga of One Taste), with are more or less empty subject, up to a very empty witness already in union with then Nondual Infinite Field. "Having" Awakenings. With any kind of content: This World, Aliens, the management & staff running this Universe, other Dimensions, whatever ones heart delights in. An Infinity (literally) of stuff to explore... What is not so often talked about is the "suicide" of stage 4, Nonmeditation Yoga, Full Enlightenment. Getting fully Impersonal with transcending/killing each and every separate-self arising having all these lovely nondual experiences/awakenings. No Aliens required, but still possibly quite a bit scary for sure. But looks only scary from before the Gateless Gate. Any separate self arising (the enlightened or awake "person"  having these awakenings, n+1) raising its ugly head, are seen as just more separate-self-contractions buzzing in Ones True Self. Another annoying little headache-bug to laugh about. Another moskito buzzing around in the Infinite Reality that one then realizes onself to be and ever having been, to squatt/Trekchö. One more contraction to let go and transcend. and one lucky day, one just wakes up. But death is death, transcendence is death, even if its only the death of an Illusion. And Maya needs her tools, like the Wizard of Oz, else everbody would just say bye bye to the game. [Disclaimer: In nearly all cases, real suicide is about the most stupid thing one can do. Back to square 1, more Karma added on top. Or how to continue the dream, dodging out ones Karma of this life, with additional Karma on top from hitting the reset-button. But no soul gets lost, just do 3rd grade again, with a headache-hangover from the last try. Finally, every soul graduates college. But some like school so much that they don't listen to most teachers, and do some classes over and over again]. So, have fun on the trip, don't fry your brains, keep your humor (Wilber, Transcendence restors humor), squatt all separate self bugs,  and Bon Voyage!  Selling Water by the River   Ken Wilber wrote: “TRANSCENDENCE RESTORES HUMOR. Spirit restores humor. Suddenly smiling returns. Too many representatives of too many movements – even many very good movements, such as feminism, environmentalism, meditation, spiritual studies – seem to lack humor altogether. In other words, they lack lightness, they lack a distance from themselves, a distance from the ego and its grim game of forcing others to conform to its contours... They should all trade two pounds of ego for one ounce of laughter”(Ken Wilber. 1999. One Taste: The Journals of Ken Wilber. December 7).   PS: And for all other beings/perspectives of Indras Net, see: and if you don't already have an overkill, and better go for nice walk or so...  Some more for the Aficionados of conceptual overkill: And now, really better go fishing or something... “frog pond plop”