Hello, T4r4sB, you wrote: TB> But the essence of a tautology, principles of its operation, whether are they something to the higher, above laws of any Universe, or they can be broken? Not, anything the higher it is not. We consider, for example, a tautology "2+2=4". Its sense that if "2" it that we mean when we we draw this flourish if "+" it too about what we already agreed, and the same with "=" and "4" to the expression we inevitably should attribute a predicate "true". If, of course, "expression", "predicate", "attributing" and "true" is about what we agreed. Thus the validity "2+2=4" at all does not guarantee that if we put "2+2" to a real reality situation, we will have "4". For example, if we plant in one cell two rabbits and two doe-rabbits in half a year in this cell we find not mandatory 4. Or if on Monday in the street there were 2 degrees and on Tuesday too 2 it does not mean that in the beginning of week there were 4 degrees. In any way it is impossible to use an in itself tautology. But if it to cross the fact (which absolutely reliable piece on determination not is, and it is capable to be true, and then , and it appears that it false, or on the contrary) tautologies become tools. For example, supplying "2+2=4" it is comprehensible by a reliable hypothesis that rabbits have not time to be multiplied, open a cell for days and solemnly to find out correspondence of the theory to a prediction. In the same way, the tautology about that the hypotenuse square is equal to the total of squares of legs, yields comprehensible result in conditions when "curvature of space to neglect". That is when freakish and infinitely various reality appears geometry adequately corresponding to axioms. To say that tautologies "above"... Well, I do not know. What we will use in an altimeter role?