Reconciling between the reports that Jibreel, Adam and Muhammad (blessings and peace of Allah be upon them) sawParadise, and the hadeeth “… that which no eye has seen…”

It is well known that in Paradise there is that which no eye has seen
and no ear has heard, but wasn't Adam in Paradise? Didn't the Prophet
(blessings and peace of Allah be upon him) enter Paradise too?.
Praise be to Allaah.
Firstly:
It was narrated from AbuHurayrah (may Allah be pleased with him) that
the Prophet (blessings and peace of Allah be upon him) said: "Allaah
says: 'I have prepared for My righteous slaves that which no eye has
seen, no ear has heard and it has never crossed the mind of man. All
of that is reserved, besides which all that you have known is as
nothing.' Then he recited: 'No person knows what is kept hidden for
them of joy as a reward for whatthey used to do' [al-Sajdah 32:17 –
interpretation of the meaning]."
Narrated by al-Bukhaari (3072) and Muslim (2824) -- the report
narrated by Muslim adds:"apart from that of which Allaah has informed
you."
Secondly:
With regard to the Prophet (blessings and peace of Allah be upon him)
seeing Paradise and entering it, that is proven in many hadeeths. Imam
al-Bukhaari, in his book al-Sharee'ah, quoted some of these hadeeths
under the chapter heading Baab Dukhool al-Nabi (sall Allahu 'alayhi wa
sallam) al-Jannah (The Prophet'sentering Paradise) in which he
narrated several hadeeths, including the following:
It was narrated from Anas ibn Maalik that the Prophet (blessings and
peace of Allah be upon him) said: Whilst I was walking in Paradise, I
saw a river whose bankswere domes of hollow pearls." I said, "What is
this, O Jibreel?" He said: "This is al-Kawthar which your Lord has
given to you." The angel struck it with his hand and its mud or its
perfume was of the mostfragrant (or pure) musk.
Narrated by al-Bukhaari (6201).
According to another report: When the Prophet (blessings and peace of
Allah be upon him) was taken up to heaven (the Mi'raaj), [he said:] I
came to a river whose banks …
According to a version narrated in Musnad Ahmad (19/66): "I entered
Paradise and saw a river whose bankswere pavilions of pearls."
Thirdly:
With regard to the issue mentioned by the questioner, it may be said:
This that has been prepared in Paradise for the righteous slaves of
Allah has not been seen by anyone, as it states in the texts. As for
what Adam and our Prophet Muhammad (blessings and peace of Allah be
upon them) saw, it was only part of in Paradise because Paradise, "in
which there is that which no eye has seen" is not necessarily that
which no one has ever seen. Rather it may be that there are in it
things that some eyes have seen, even though there is in it that which
is stored up and hidden, no eye has seen it and no ear has heard, and
noone can imagine it or describe it.
Perhaps the above meaning is supported bythe hadeeth of al-Mugheerah
ibn Shu'bah, who said: The Messenger of Allah (blessings and peace of
Allah be upon him) said: "Moosa asked his Lord: 'Who will be the
lowest of the people of Paradise in status?' He said: 'He will be a
man who will come after I have admitted the people of Paradise to
Paradise and it will be said to him: "Enter Paradise." He will say: "O
Lord, how, when the people have taken their places and been given
their portions?" It will besaid to him: "Would it please you if you
had the like of what one of the kings of the world had?" He will say:
"I would be pleased, O Lord." He will say, "You will have that, and as
much again, and as much again, and as much again, and as much again."
The fifth time, he will say, "I am pleased, O Lord." He will say: "You
will have that and ten times as much, and you will have what your
heart desires and what will delight your eyes." He will say: "I am
pleased, O Lord."' (Moosa) said: 'My Lord, who will be the highest of
them in status?' He said, 'They will be the ones whom I have chosen,
and I have planted their honour with My own hand. I have set a seal
over it and no eye has seen, no ear has heard, nor has it entered the
heart of man.'" He said: And the confirmation thereof is in the Book
of Allaah, may He be glorified and exalted: "No person knows what is
kept hidden for them of joy as a reward for what they used to do"
[al-Sajdah 32:17].
Narrated by Muslim, 189.
It is as if those who are highest in status are those who have the
greatest share of this hidden treasure and blessing that no eye has
seen and no mind has imagined.
And Allah knows best.