Aligning your views with someone else's may require changes to both sets of views (yours and theirs), which could involve negotiation. Consider two people planning a trip, each compromising slightly to achieve a plan they are both happy with.
It's about whether the discussion is general (valid for anyone) or specific (these people, here, now). The latter gives some weight to subjective arguments and arguments from authority, the former does not, and this is a big qualitative difference.