Re: reductio ad falsum versus reductio ad absurdum

OH i get it! constructive reductio ADDS (introduces) a tilde, and IP
removes (eliminates) one. they are only equally powerful if you have
DN (double negation).

.

Relevant Pages

  • Re: eg
    ... A tilde should mean "approximate", ... > two character sets, they decided to map between those two vaguely ... of tilde as negation must go back further than this, ... Many introductory books still do use that horrible notation ...
    (comp.text.tex)
  • Re: eg
    ... Donald Arseneau wrote: ... of tilde as negation must go back further than this, and probably had something to do with what symbols were available on Bertrand Russell's typewriter or something. ...
    (comp.text.tex)
  • Re: removing zeros from a vector
    ... Jeremy Smith wrote: ... What is the double tilde for in the following statement? ... It's a matlab trick to get a logical vector with trues when A is not ...
    (comp.soft-sys.matlab)