Question

Hello Rabbi, a few questions:
 
1) If a person observes commandments because that’s what is written in the Torah, is careful with even the minor ones as with the major ones, but does not believe that their source is God—does that count as observing commandments? (His reason is folkloristic, or some other strange reason.)
2) If a person observes rabbinic commandments because one must listen to them according to the Torah, he intends to fulfill the commandment of “and you shall do according to what they instruct you,” but in his mind he is dismissive of the commandment and of the reason for the commandment (the rabbinic one)—is he considered to have fulfilled the commandment?
3) I assume you’ve written about this before, but I don’t know where: why is the rabbinate today not considered “and you shall do according to what they instruct you”? Maybe you’ll say that ordination was simply lost, and therefore there is no Sanhedrin either, in which case I’ve answered myself. Is there another reason? Why shouldn’t we listen to them under the principle of “the law of the kingdom is the law,” and simply say that since the state recognizes them as the religious authority, one should listen to them as a religious authority? (Maybe the state itself doesn’t listen to them in some matters, and then of course I haven’t said anything.)
 
4) Does “make for yourself a rabbi,” according to Tractate Avot, obligate me to follow the rabbi I have “made” for myself?
5) For the future, do you prefer that each question be asked in a separate post?