5.5321
Instead of “(x):fx⊃x=a” we therefore write e.g. “(∃x).fx.⊃.fa:~(∃x,y).fx.fy”. And if the proposition “only one x satisfies f( )” reads: “(∃x).fx:~(∃x,y).fx.fy”.
Instead of “(x):fx⊃x=a” we therefore write e.g. “(∃x).fx.⊃.fa:~(∃x,y).fx.fy”. And if the proposition “only one x satisfies f( )” reads: “(∃x).fx:~(∃x,y).fx.fy”.