22/05/04 10:20:25.57 jd9HfROA.net
ロバーツの指摘を再記しておきます
An exercise in colimits,
contra Mochizuki
D.Roberts
2021.11.22
「referencing this document,
(ON THE ESSENTIAL LOGICAL STRUCTURE OF INTER-UNIVERSAL OF LOGICAL AND “∧”/LOGICAL OR “∨” RELATIONS)
whichis, to say the least, not a mathematical justification of any part of IUT.
Anyway, in case there are people who think Mochizuki can do no wrong, I wrote out a complete and elementary construction, with proof, of the projective line, using no “redundant” copies of the affine line.
It uses the standard definition of pushout (=a gluing construction) from Mac Lane’s classic textbook Categories for the Working Mathematician, and the usual definition of the projective line.
It is not terribly interesting, but someone had to do it.」
「I maintain, with good reason, that the type of reasoning in the note is
what the so-called ‘RCS’ is doing.
It is standard category theory and standard mathematics. There is
no linguistic trickery or confusion
or deeply detrimental disruptions here. Mochizuki is using nonstandard
definitions of standard terminology, and then complaining that other people’s definitions (which are the standard ones) lead to contradictions.
They really don’t, if one doesn’t insist on trying to ignore the differences, and I don’t understand why he persists in it.」
URLﾘﾝｸ(thehighergeometer.wordpress.com)