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Common Descent rests squarely on a specific view of the origin of life.

I submit five hypothesis regarding the origin of the first life forms.

a) Natural processes occuring entirely upon earth resulted in chains of self-replicating molecular strands that eventually became the first life forms.

b) Aliens from another planet and/or dimension travelled to this planet and -- deliberately or accidentally -- seeded the planet with the first life forms.

c) In the future, humans will develop a means to travel back in time. They will use this technology to plant the first life forms in Earth's past, making the existence of life a causality loop.

d) A divine agent of unspecified nature zap-poofed the first life forms into existence.

e) Any method other than the four described above led to the existence of the first life forms.

If, as you say, common descent "rests squarely on a specific view of the origin of life", then only one of the above hypothesis can be true for common descent to have occured. Please identify which of the five must be true for common descent to have occured, and explain why any two of the other options would prevent common descent from occuring.

"If, as you say, common descent "rests squarely on a specific view of the origin of life", then only one of the above hypothesis can be true for common descent to have occured."

Bzzzzzzzt. Wrong. Bad logic, try again.

My point was that if you remove assumptions about the origin of life, then your assumptions don't require you to posit monophyly. Then all you have is the evidence. Incidentally, as the paper I referenced points out, the evidence doesn't require it, either, and actually speaks against it in many ways.

Again, without specific assumptions about the origin of life, there is no reason to assume monophyly. That is not the same thing as saying that only one set of assumptions will get you monophyly. The point is that if you don't make origin-of-life assumptions, you do not get monophyly from the data.