Going to fourth density? Or fifth?

[Tenet Nosce]

Why? Landscape is your experience.

Because our consciousness acquires another dimension of motion. This allows for different views of the landscape.

No new 3D natives are born into 3D.

So then 3D ends when the last 3D native dies, but there is otherwise a total continuity of experience?

There would be more transparency in thought (motives, desires, etc), for example.

What do you suppose will be the effects on 3D bodies?

What makes something ironic? Why something is aesthetically pleasing or fashionable? What makes the ego feel safe and not safe?

What do these have to do with the planetary mind?

Sure they can, after 4D sphere is fully formed due to use by inhabitants. It's in an entirely different dimension.

So 4D instreaming begins shortly. Use of 4D catalyst by 3D/4D hybrids literally forms the 4D sphere during the "transition period" which is variable dependent upon how efficiently the catalyst is used. Meanwhile, 3D entities live out their lives and upon death await the 4D sphere to be completed, or are transferred to another 3D sphere.

What determines when 4D becomes inhabitable?