Faith is regarded as lacking certainty and is distinct from what we usually refer to as knowledge. Certain philosophers, such as Soren Kierkegaard, have argued that rationality has little to do with it: what matters most of all is faith, which is, quite simply, an irrational commitment. Reason and faith work together, one giving justification for the other. Kierkegaard was critical of reasoned argument because each generation has shown that much of what it reasoned to be the case has been shown to be otherwise. Undoubtedly, there is much appeal to this romantic concept of the self-righteous individual against the power of abstract reason and what he called the 'public'. What Kierkegaard was concerned with was to provide meaning in what would otherwise be a meaningless world. Christian belief, such as the incarnation or the trinity, is undoubtedly paradoxical because, by its nature, it must be.