An attempt to reevaluate the intellectual beginnings and basis of modernism and, in so doing, to provide the next century with a more humanistic outlook--one to counter What the author sees as a pervasive and increasingly and rationalism. In his provocative but sometimes facile argument, Toulmin (Humanities/Northwestern) further delineates today's modernist and postmodernist views. Toulmin makes much of his thesis that modernism had two intellectual origins. First, he argues, there were the 16th-century Renaissance humanists such as Montaigne and Shakespeare; then followed the 17th-century rationalists such as Descartes and Newton. From 1630 on, Toulmin discovers, the second group predominated among intellectuals who, amidst a background of religious strife, sought to erase the earlier emphasis on human ambiguity and comprehensive rational theories of society. ""Cosmopolis""--a reason-based vision of man and society--was to hold sway for the next 300 years as the initial humanist strain went into partial eclipse. What is needed for the next century, Toulmin states, is the rebirth of humanist thinking with its classical skepticism to complement--not compete with--today's overly burdened rational and scientific thinking, Success here would intertwine the sciences and liberal arts and thus bridge the rift in 20th-century thought that C.P. Snow analyzed in his classic Two Cultures. Much of Toulmin's claim to originality depends on his convincing the reader that the 17th century has until recently been widely perceived as the source of intellectual modernism. But many will dismiss this Claim, having themselves long seen a continuity between today's liberal arts and the earlier Renaissance. So, they might ask, What is really new here?