Now certainly after Eve partook of the fruit it was impossible for Adam to keep both (since Eve would be kicked out), but I wonder if it would have been possible to keep both commandments if Eve had not partaken.
It seems odd to me that God would give commandments that conflict with eachother. I find it easier to belive the idea that the fall was the only way was a lie of Satan.
Perhaps if they had waited, they could have progressed to a point where they could have taken it with God's approval and they (and we) would have entered mortality with the maturity to avoid choosing evil, making it possible to live a sinless life as Christ did.
This is all of course just my own musings on the topic and is very speculative. If any of you other LDS freepers have any official sources that confirm or deny any of this I would love to see it, but I doubt there is anything known about what would have happened if Eve did not partake since the whole thing is moot anyway.
According to Brigham Young, eating food composed of the elements of this world is what enabled them to finally be able to have children:
"After men have got their exaltations and their crowns -- have become Gods, even the song of God --are made Kings of kings and Lords of lords, they have the power then of propagating their species in spirit; and that is the first of their operations with regard to organizing a world. Power is then given to them to organize the elements, and then commence the organization of tabernacles. How can they do it? Have they to go to that earth? Yes, an Adam will have to go there, and he cannot do without Eve; he must have Eve to commence the work of generation, and they will go into the garden, and continue to eat and drink of the fruits of the corporeal world, until this grosser matter is diffused sufficiently through their celestial bodies to enable them, according to the established laws, to produce mortal tabernacles for their spiritual children." -- Journal of Discourses, Remarks by President Brigham Young at a Special Conference held in the Tabernacle, Great Salt Lake City, August 28, 1852.
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