ed ▁on ▁January ▁ 8 , ▁ 2 0 1 2 ▁here ▁ ▁St ap leton , ▁G . ▁and ▁How se , ▁J . ▁and ▁Taylor , ▁J . ▁and ▁Thompson , ▁S . ▁What ▁can ▁sp ider ▁diag rams ▁say ? ▁Pro c . ▁Di agr ams , ▁( 2 0 0 4 ) ▁v . ▁ 1 6 8 , ▁p .   1 6 9 – 2 1 9 . ▁Access ed ▁on ▁January ▁ 4 , ▁ 2 0 1 2 ▁here ▁ ▁St ap leton , ▁G . ▁and ▁Jam nik , ▁M . ▁and ▁Mas th off , ▁J . ▁On ▁the ▁Read ability ▁of ▁Di agram m atic ▁Proof s ▁Pro c . ▁Autom ated ▁Re ason ing ▁Work shop , ▁ 2 0 0 9 . ▁PDF ▁ ▁External ▁links ▁▁ ▁Bright on ▁and ▁Kent ▁University ▁- ▁E uler ▁Di agr ams ▁ ▁Category : Di agr ams ▁Category : Di agram ▁al gebras <0x0A> </s> ▁Roy ▁Ger ald ▁Fitz ger ald ▁( August ▁ 2 5 , ▁ 1 8 7 5 ▁– ▁November ▁ 1 6 , ▁ 1 9 6 2 ) ▁was ▁an ▁att orney , ▁soldier , ▁pres ervation ist , ▁and ▁a ▁member ▁of ▁the ▁United ▁States ▁House ▁of ▁Representatives ▁from ▁Ohio . ▁ ▁B irth ▁and ▁early ▁life ▁He ▁was ▁born ▁in ▁Wat ert own , ▁New ▁York ▁and ▁moved ▁to ▁Day ton , ▁Ohio ▁with ▁his ▁parents , ▁Michael ▁Ger ald ▁and ▁Corn elia ▁Maria ▁(