Okay, forget Asimov then. Uta Ranke-Heinemann, a professor of religious history at the University of Essen (Germany) (In case there’s any question about her authority in this matter) finds rational reasons for doubting the “census migration” story as well. I’ll try to summarize the major points :
First, the idea that Ceasar himself ordered the census is ludicrous. It would have unleashed a wave of international migration and as a way of assessing taxes would have been completely unworkable. The census was ordered by Quirinius, (the one that we have records of and which Luke references) but it was not nationwide.
Secondly, according to Roman Law the declaration had to be made in the place where the person resided, or in the case of property owners, where he owned property, not where a person was born.
Thirdly, there would have been no motive for Joseph going to Bethlehem since he was a native of Galilee. Since Galilee was under the auspices of the tetrarch Herod, Joseph would have been under no obligation to an edict issued by a Syrian governor. It’s pretty obvious that Joseph was a poor person; if he were a rich landowner, he would have had tenants and serfs and could have seen to it that Jesus was born at one of those houses rather than in a manger.
Fourthy, even if Joseph WAS rich and did have to go, there was no reason for Mary to go along as only the head of the household was responsible for declarations for taxation.
Fifthly, and lastly, Joseph going to Bethlehem because “he was of the house and lineage of David” meant absolutely nothing to a Roman emperor. Jewish lineage was a matter of complete indifference to the Roman state.
Saint Sutychus H.M.S.H.
" ‘He is a prince’ , the minstrels sing.
Among men, yes. Among fools he is a king."
Disney Shorts
The Eutychus Papers