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Just a layman and slow learner. Thank you for your enlightenment and patience, and for giving me the best memory in my life.


Jul
21
comment Are variables logical or non-logical symbols in a logic system?
thanks. (1) I mixed up variables for the arguments to quantifies, and variables representing propositions. (2) the former is non-logical, while the latter is logical symbols, according to en.wikipedia.org/wiki/Non-logical_symbols
Jul
21
asked Relations and functions with valence 0
Jul
21
accepted Are variables logical or non-logical symbols in a logic system?
Jul
21
asked Can True and False be represented without quantifies?
Jul
21
revised Are variables logical or non-logical symbols in a logic system?
added 75 characters in body
Jul
21
comment Are variables logical or non-logical symbols in a logic system?
I understand constants are 0-ary logical operation symbols. But why are variables logical symbols?
Jul
21
asked Are variables logical or non-logical symbols in a logic system?
Jul
21
comment What does “calculus” mean?
@Arkamis: you mean "plaque"?
Jul
21
revised What does “calculus” mean?
deleted 9 characters in body
Jul
21
asked What does “calculus” mean?
Jul
20
awarded  Cleanup
Jul
20
revised theory, theorems and axioms
rolled back to a previous revision
Jul
20
comment theory, theorems and axioms
(1) "taking the theorems as axioms" or "taking the theory as axioms" (2) Is the set of axioms always recursive?
Jul
20
comment theory, theorems and axioms
@ThomasAndrews: My bad. the first question is: is the theory the set of axioms or the set of theorems?
Jul
20
revised theory, theorems and axioms
added 22 characters in body
Jul
20
asked theory, theorems and axioms
Jul
20
asked Meaning of abstractness and concreteness
Jul
19
comment Axiom Systems and Formal Systems
Thanks. +1. (1) Do "rules of formation" generate strings from nothing? (2) Are "rules of formation" the formal grammar? (3) Are "rules of transformation" used in defining a language inductively or recursively from some basic strings? (4) how do you transform between "rules of formation" or a formal grammar and "rules of transformation"? See also cs.stackexchange.com/q/28534/336
Jul
19
asked Are axioms assumed to be true in a formal system?
Jul
19
comment Is a definition either intensional or extensional?
@QiaochuYuan: do you happen to have some idea?