How it happened . . .

 Up until about the course just above the second floor joists, I pushed the logs up by hand on ramps. A little at a time each end.

After a while I had to get a little help.

1945 or so Ford Ferguson Tractor.
Still used ramps, but now had a pulley attached to a post in the middle of the cabin and pulled the logs up.
In the first photo you can just see the center pole.
In the second photo you can see the rope attached to the logs, over the pulley, and back to the tractor.