Question

Hello
All of the whole concept of presumptions seems very puzzling to me. When you learn the passages and the words of the later authorities (Acharonim), you see that following a presumption is not merely in the category of “passive omission is preferable” or “the burden of proof that there was a change lies on the other party,” but that there is actually taking a certain side regarding reality. 

1. What, in your opinion, is the explanation for this phenomenon? 
2. Can one suggest the following explanation: A person, in general, never grasps reality exactly as it is, and always relies on generalizations, etc. (he relates to a shirt as red even though it has additional parts in it as well — he follows the majority; if he heard that a certain person is healthy, he does not treat that as a point-in-time fact relevant only to the moment he heard it, but assumes that he is always healthy, and the proof is that if he later hears that he is sick, he will be surprised — why? Because until that moment he assumed he was healthy and did not relate to it as a doubt. Our psyche has a tendency not to remain in doubt and to fill in the gaps in order to feel certainty. That is the concept of presumptions — in situations of doubt (absence of knowledge), a person defines reality on the basis of the data known to him — we do this without even noticing. When we follow presumptions, the intention is not that this is an objective clarification. There is a meaningful statement here by the Torah — the Torah was given to human beings, and the definition of situations is not made on the plane of objective clarification (since man is not capable of doing this, as we have already explained — he always tends toward generalizations and assumptions), and the Torah says that it goes along with this. Therefore presumptions, majority, etc. are not objective clarification, but clarification in the sense that this is generally how a person encounters reality. According to this, one can explain why a presumption that was not established at its proper time is weaker than ordinary presumptions.
   As we already said — the clarification of presumptions is not an ordinary objective clarification, but the way a person encounters reality — therefore it matters that the presumption exist at the time of the doubt, when the person encounters reality. However, if the presumption exists only afterward, then when a person uses the presumption, he does not experience reality through it, but rather analyzes the past by means of it, and then this is objective clarification rather than subjective clarification, and therefore a presumption, which is a subjective clarification, should not be effective.