It is argued in this paper that a greater understanding of dualism is needed to secure the future of humanism and of humanity. Its study consists in understanding the extremes of opinion and attitude to which we are all prone and which pervade every aspect of our society. These extremes are even today impeding our future and threatening to plunge the world into internecine struggles between factions competing for power and pre-eminence. The fruitless conflicts, wars and divisions caused by extremism will only be avoided when a dualist view is adopted that makes the ‘either-for-us-or-against-us’ mentality universally unacceptable. The dualist view also helps us to deal with situations that demand insight more than logic. A distinction is made here between naïve and systematic dualism in which the former refers to confused and muddled thinking whereas the latter involves organized and purposeful thinking to deal systematically with confusing and conflicting situations. There is a spectrum between naïve dualism at one extreme and absolute monism at the other extreme. Most of us, most of the time, are systematic dualists subsisting somewhere in the middle. Our future is constantly threatened by those few people who have one answer to everything and are intolerant of other views. If the dualist view becomes prevalent they may learn to think differently. Humanism is distinct from religion in being essentially dualist in its outlook and in being prepared to countenance alternative views. The further development of the dualist view therefore strengthens humanism against its monist enemies who are looking for certainty and easy solutions.