Another indication of an Egyptian philosophical tradition would be some examples of sceptical literature.
Egyptian ideas did develop and change many times during its long history.
If you don't accept that Egypt was a dynamic culture then try to read some new research on Egyptian theology.
but first take a look at:
"Rebel in the Soul: An Ancient Egyptian Dialogue Between a Man and His Destiny
by Bika Reed (Author) "I spoke to my Soul I replied to what it had said: O! Now this I cannot bear My Soul replies not Indeed, worse than..."
For more information on the Egyptian "Ba" see:
Reeder, G, (1999) "Musing on the sexual nature of the human headed Ba bird" KMT, Autumn pp72-78