How "rational" is "rationality"
By tak ing se ri ous a re mark once made by Paul Bernays, namely that an account of the na ture of ra tio nal ity should be gin with con cept-for ma tion, this ar ti cle sets out to un cover both the re stric tive and the ex pan sive bound aries of ra tio nal ity. In or der to do this some im pli ca tions of the pe ren nial philosoph i cal prob lem of the "co her ence of irreducibles" will be re lated to the acknowl edge ment of prim i tive terms and of their indefinability. Some crit i cal re marks will be ar tic u lated in con nec tion with an over-es ti ma tion of ra tio nality -con cern ing the in flu ence of Kant's view of hu man un der stand ing as the for mal law-giver of na ture (the sup pos edly "ra tio nal struc ture of the world"), and the ap par ently in no cent (sub jec tiv ist) habit to re fer to ex pe ri en tial en tities as 'ob jects'. The other side of the coin will be high lighted with ref er ence to those kinds of knowl edge tran scend ing the lim its of con cept-for ma tioncul mi nat ing in for mu lat ing the four most ba sic idea-state ments phi los o phy can ar tic u late about the uni verse. What is found "in-be tween" these (re strictive) and (ex pan sive) boun d aries of ra tio nal ity will then briefly be placed within the con tours of a three fold per spec tive on the self-in suf fi ciency of logi cality -as merely one amongst many more di men sions con di tion ing human life. Al though the mean ing of the most ba sic log i cal prin ci ples -such as the log i cal prin ci ples of iden tity, non-con tra dic tion and suf fi cient rea sonwill sur face in our anal y sis, ex plor ing some of the com plex is sues in this respect, such as the re la tion ship be tween thought and lan guage, will not be ana lysed. The im por tant role of sol i dar ity -as the ba sis of cri tique -will be ex plained and re lated both to the role of im ma nent crit i cism in ra tio nal conver sa tion and the im por tance of ac knowl edg ing what is des ig nated as the prin ci ple of the ex cluded antinomy (which in an ontic sense un der lies the logi cal prin ci ple of non-con tra dic tion). The last sec tion of our discussion will suc cinctly il lu mi nate the proper place of the in ev i ta ble trust we ought to have in ra tio nal ity -while im plic itly warn ing against the ra tio nal is tic over-es ti mation of it (its de gen er a tion into a ra tio nal ist "faith in rea son"). Our in ten tion is to en hance an aware ness of the re al ity that ra tio nal ity is em bed ded in and bor ders on givens which are not open to fur ther "ra tio nal" ex plo ra tiongivens that both con di tion (in a con sti tu tive sense) and tran scend the lim its of con cep tual knowl edge. Some of the dis tinc tions and in sights op er a tive in our 1 An ear lier ver sion of this pa per was pre sented at the An nual Phi los o phy Con fer ence of the Philo soph i cal So ci ety of South ern Af rica, Rhodes Uni ver sity, Grahams town, Jan u ary 2003. 248 S. Afr. J, Philos. 2003, 22(3) 2 "The de vel op ments in the foun da tions of math e mat ics since 1900 are be wil der ing, and the pres ent state of math e mat ics is anom a lous and de plor able. The light of truth no lon ger il lu mi nates the road to fol low. In place of the unique, uni ver sally ad mired and uni ver sally ac cepted body of math e mat ics whose proofs, though some times re quir ing amendation, were re garded as the acme of sound rea son ing, we now have con flict ing ap proaches to math e mat ics. Be yond the logicist, intuitionist, and formalist bases, the approach through set the ory alone gives many op tions. Some di ver gent and even con flict ing po si tions are pos si ble even within the other schools. Thus the constructivist move ment within the intuitionist phi los ophy has many splin ter groups. Within for mal ism there are choices to be made about what prin ci ples of metamathematics may be em ployed. Non-stan dard anal y sis, though not a doc trine of any one school,
