My second density cat can see and touch me.

[anagogy]

So why dont we see all the various forms that supposedly do not make this choice? Do you think that any being of anothet density could instantly make themselves visible.

Although 4D is treated as distinct from 3D, they both are always existing.

Ra has also stated that it requires concentration for a 4th density being to appear in 3rd density. "It is possible for fourth density to be visible. However, it is not the choice of the fourth-density entity to be visible due to the necessity for concentration upon a rather difficult vibrational complex which is the third density you experience."

I would think that once they achieve social memory, it doesn't take long for them to all collectively agree not to attempt to walk upon the 3rd density plane. It sounds, from Ra's description, that it is uncomfortable for them anyhow, so there wouldn't be too many attempting this anyhow.

There is also the matter of the law of confusion/free will. We could also relate this same law to the "law of attraction". Beliefs create reality, and those who sincerely and purely "disbelieve" would repel the experience of any evidence to the contrary.

For two realities to interact there has to be a common vibrational ground to stand on. Even when Ra clothed themselves in 3rd density visible bodies in Egypt, they could only appear because the people they were appearing to already had an "all-embracing belief in the live-ness or consciousness of all."

Otherwise, such an appearance would have been infringement and negated by the law of confusion/free will.