Many readers of science fiction have a theory of “accessibility” that is absolute, static, essentialist, substantive, and nevertheless unduly personal. Let’s call it T1.
T1: is accessible (by implication: in general) that which I found accessible at the moment I read it.
My own theory of accessibility is relativist, historical, contingent, tautological, and impersonal.
T2: is “accessible” that which is accessible to someone in a context that is changing, multiple, singular, and non-universalisable.
Thus, accessibility-1 ≠ accessibility-2
For example, I read DUNE at a relatively young age (14), and I found it immediately accessible. Today Denis Villeneuve is obliged to create a dumbed-down DUNE, without inner dialogue (i.e. not DUNE at all) to make it “accessible” (for the public to delude itself that it has access).
I deal with the example of DUNE from the point of view of the relativity of accessibility in greater detail here:
Xeno Swarm 
Hi Terence, what a wonderfully clear exposition of Dune, locating it in our time of “post just about everything”. Dune was/is one of my favorite SF’s of all time, along with Stranger in a Strange Land! I read them both as a young man (in Sydney no less) in the 70’s and was enchanted. Your literary piece here helps me understand what the enchantment was (at the time I had none of this vocabulary). It was about my/our future!
I picked out just a few gems:
“A strange reason, an estranging and estranged cognition, in essential relation to uncertainty, multiplicity, and chaos.”
And as the ancient Hesiod myth teaches, the first born of chaos is eros, the one who makes fresh connections from chaotic elements, or as you say, “A new field arises out of this like a spirit rising from a witch’s cauldron”, or, “the approach of a coherence that is neither ours, that of humans, nor that of God or the world.”
Thanks so much, Terence, for this, Cheers, John (sorry if this submission is repeated)
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