Against unknown?

 Corinthians 2:14-15, which says that "a physical man does not receive the things of God," but that "the spiritual man examines indeed all things." The JW should agree that what Paul means is that a physical man without God's 

The word spirit can have a number of different usages it can refer to a spirit person but it need not. It can also refer to the inner mental life that might be inaccessible to onlookers see Hebrews ch.4:12 or indeed it may refer to the Holy Spirit. Here the contrast is between mindsets there is a mindset that results from submitting to/being led by the spirit and it is being contrasted with the mindset that results from submitting to/being led by the flesh JEHOVAH doesn't give his spirit to Just anyone he gives to to those hungering for it spiritual people

1Corinthians ch.2:11KJV"For what man knoweth the things of a man, save the spirit(mind) of man which is in him? even so the things of God knoweth no man, but the Spirit(mind )of God."

1Corinthians ch.2:12KJV"Now we have received, not the spirit(Mindset) of the world, but the spirit(mindset) which is of God; that we might know the things that are freely given to us of God"

So we are not dealing with a contrasting of essential natures because both the fleshly man and the spiritual man have the same essential nature but the spiritual man has chosen to pursue a relationship with JEHOVAH And the fleshly man has chosen to pander to the flesh

This spiritual mindset is not an essential nature it can be lost if not carefully curated likewise there is always the hope that one with a fleshly mindset can come to realise futility of attempting to satisfy the flesh and begin a sincere search for the truth.

Matthew ch.11:25NIV"At that time Jesus said, “I praise you, Father, Lord of heaven and earth, because you have hidden these things from the wise and learned, and revealed them to little children. "

Unknown:without the Spirit will not accept the truth of God's word. Yet the contrast here is between the exact same two words (in Greek as well as in English, as can be shown using the JWs' Kingdom Interlinear Translation if necessary). Clearly, the "spiritual" man in this text has not ceased to have physical existence; the point is that the ultimate source of his life is different from that of the (merely) physical man. In like manner the "spiritual" body of 1 Corinthians 15:44 is not an immaterial body, 

we know that all words can be used in a variety of senses so is the word pneumatikos/spiritual being used in the same sense at both  1corinthians ch.15:44 and 1Corinthian ch.2:14,15 one way to tell would be to carefully examine the respective contrasts that are being made

At 1Corinthians ch.2:14,15 it is two mindsets and not two essential natures that are being contrasted

While at 1Corinthians Ch.15:44 it is the essential nature of the body that is sown that is contrasted with the essential nature of the body that is raised up.

Unknowned:but one that is energized or enlivened by the Spirit in a way that it was not beforehand. And so this verse also is a prooftext for, and not against, the physical resurrection of Jesus.

 It does seem that Paul was alluding to a change of essential natures though

1Corinthians ch.15:45KJV"And so it is written, The first man Adam was made a living soul; the last Adam was made a quickening spirit."

It is important to note both what is said and what isn't said

It is said that the man was MADE a soul it is not said that the man received a soul so the man is a soul rather than possessing a soul

The same statement is made of the lower lifeforms they too are referred to as psyche/nefesh

Genesis ch.1:21KJV"And God created great whales, and every living creature(Psyche/Nefesh) that moveth, which the waters brought forth abundantly, after their kind, and every winged fowl after his kind: and God saw that it was good."

Likewise it is not said that the last Adam received a spirit but that he BECAME a spirit the same word is used of angels

1Chronicles ch.18:21ASV"there came forth a SPIRIT, and stood before JEHOVAH, and said, I will entice him. And JEHOVAH said unto him, Wherewith?"

Just as the first Adam was not a Soul before becoming such neither was the last Adam spirit before BECOMING such

Think of Fred who goes to medical school and becomes a doctor there is no concrete distinction between Fred and the doctor that he has BECOME thus if Fred dies it would be understood that the doctor that he had become died.

And what does it mean for a soul to die it simply means that that soul has RETURNED to its pre-creation state:

Genesis ch.3:19NIV"By the sweat of your brow

you will eat your food

until YOU(not your body) RETURN to the ground,

since from it you were taken;

for dust YOU(not you body) are

and to dust YOU(not your body) will RETURN.”

Though the bodies possessed by spirit beings are essentially intangible ,invisible and certainly not humanoid. they can materialise bodies that look indistinguishable from humans

Luke ch.24:4ASV"And it came to pass, while they were perplexed thereabout, behold, two men stood by them in dazzling apparel: "

Such materialisations would not only explain his tangibility on occasion but also his mysterious appearances and disappearances

Luke ch.24:31 ASV"31And their eyes were opened, and they knew him; and he VANISHED out of their sight."

Luke ch.24:31ASV"And as they spake these things, he himself stood in the midst of them, and saith unto them, Peace be unto you. "

Thus the fact that Jesus could be visible and tangible if he chose to (at least before his glorification)

Does not disprove that his essential nature was spirit but his appearances and disappearances at times in forms that were not recognisable to his disciples

Suggest that he had exchanged his human perfection for superhuman perfection.

John ch.20:14NIV" At this, she turned around and saw Jesus standing there, but she did not realize that it was Jesus."

The best Son a mother ever had and she did not recognise him.

John ch.21:4NIV"4Early in the morning, Jesus stood on the shore, but the disciples did not realize that it was Jesus."

They had known him their whole lives, if there is one person that you would think would be easily recognisable to friend and foe alike it would be Jesus Christ.

2Corinthians ch.5:1NIV"For we know that if the earthly tent we live in is destroyed, we have a building from God, an eternal house in heaven, not built by human hands."

Note there is no remodelling of the earthly house it is destroyed and replaced by a heavenly one the prospect of human perfection is exchanged for superhuman perfection.