At various times, Gef announced: “I am an earthbound spirit.” However, he is also recorded as having stated: “I am not a spirit. I am just a little extra clever mongoose.”
In addition, when commenting on a book on poltergeists that Jim Irving had been reading, Gef remarked: “I am not one of those.”

Does this tend to offer evidence in favour of – or against – Gef’s identity as that of a ghost or a spirit?

It was also noted by Fodor that “Gef dislikes all references to ghosts and spirits, and upon one occasion compelled Irving to tear up a book of ghost stories.”

So, is all this evidence of his being a spirit – but one who was, at times, in denial of the fact?

Or simply that he was unaware of his state? (there are several instances of psychics who, when in visiting  a haunted house and establishing contact with a ghost, have to explain to them that they are dead, and that they no longer belong on this earthly plane and need to move on…)

Alternatively, one could interpret Gef’s statement that he was not a spirit as simply the truth – that he was, instead, some other physical, corporeal entity (a weasel or mongoose?) who had, marvellously, learned to speak.

A third possibility is that Gef was merely misleading people deliberately so as to lead people up the garden path by making contradictory statements. Such obfuscation for fun has often been noted as a characteristic of similar entities…