The Pensées by Blaise Pascal notes for an apology of the Christian religion. And more significantly, Man is at the centre of Pascal's apology in two ways: his approach is based on the psychology of man and it is human nature that he uses as his main argument. However, the primary means which Pascal uses to arouse the "libertin" from his lethargy is the spectacle of the dual nature of man. Man is characterised both by "grandeur" and "misery", and Pascal develops the paradox of man with a view to reducing the "libertin" to a state of utter perplexity.

The "libertin" should now be ready to seek the truth without passion. Pascal shows him that neither the philosophies nor the religions of the world can explain the contradictions of human nature, or serve as a reliable guide to life. Reason is of no help, God and nature being incomprehensible. None of the three basic philosophies - stoicism, epicureanism and Pyrrhonism - corresponds to the reality of human nature. Stoicism lays too much stress on the "grandeur" of man; epicureanism overestimates his baser instincts; Pyrrhonism is unsatisfying because, although we cannot prove anything, we instinctively believe that truth exists. The religions of the world are no more satisfying than the philosophies - none can explain the mystery of human nature.

At this point, however, Pascal draws the attention of the "libertin" to the Jews and the Bible. There, one learns that the world was the work of God, and that man, created by God in his own image, fell from Grace by the misuse of his free will. There, in the doctrine of the Fall and Original Sin, is the key to the paradox of the "grandeur" and "misery" of man.

In placing man at the centre of his apology for Christianity, Pascal is very much of his age; and it is precisely because he did so that we read the Pensées today. His portrayal of the human condition remains as valid and as powerful as it ever was.

Human nature, in his opinion, can be summed up in three words - "inconstancy, ennui, anxiety." Man is changeable and inconstant, capable of laughing and crying at the same time, fickle in every sense of the word. He is naturally bored, aware of the vanity of human life. Hence we cannot live in the present, but are always looking forward or backward.

The pre-eminent quality of man is his reason; and yet reason plays little part in our lives. Reason has nothing to do with the great events of history. A fly can cause the loss of a battle; Cromwell would have ravaged Christendom and established a new dynasty but for the grain of sand which brought his death. Love can change the course of history, and its origin is an inexplicable je ne sais quoi. Reason has nothing to do with the most important decisions in our own lives. Habit is an important factor in our beliefs.

We take our ideas of right and wrong from the society around us. These vary from country to country - the Swiss set more in store by commoners than by noblemen; in France, it is the other way about. Prevalent ideas of morality are far from national: murder is wrong, and yet it is thought just to kill a foreigner in war.

Although men are creatures of reason, they do not behave rationally. We feel deeply about trifles, devote our lives to the pursuit of vain objects, such as rank, or wealth and learning, neither of which we can possess securely. Learning in any case is useless. Our motive is less a genuine desire to do these things than a desire to show off: no one would travel without an opportunity to talk about his travels later. "Glory" is such a potent motive that we prefer it to life itself.

Human judgement is fallible. Our tastes are not rational. We like or dislike a thing first, and find reasons to justify ourselves afterwards. Reason is easily swayed by extraneous circumstances. The buzzing of a fly or the creaking of a weathercock or a pulley can throw us off our balance, and it is practically impossible not to be influenced, one way or the other, by the judgement of others. Other sources of error are sickness, self-interest, and imagination - it is difficult, for example, to listen seriously to a sermon if the preacher is funny-looking or has a disagreeable voice, or to keep one's head on a narrow plank over an abyss.

There are many signs of the fallibility of human reason. We are never sure of our sanity. Philosophy has never achieved any certainty over anything, not even about what constitutes the "highest good". Reason must not be trusted too far. Like La Rochefoucauld, Pascal thinks that at times it is better to be mad than sane. Reason must not be rejected, but its limitations must be acknowledged; we must recognise that many things surpass our understanding.

Human nature is dispassionately analysed by Pascal. Men are egoistical, full of self-love, full of faults which, however, they are unwilling to acknowledge, so that they are continually playing a part and being hypocritical. Society - here again Pascal is at one with La Rochefoucauld - could not exist without this hypocrisy. Human nature is naturally vicious, animated by concupiscence. Our seeming virtues are but vices - here again we recall La Rochefoucauld; pity, for instance, is a form of self-interest. Sometimes virtue is merely the balance between two contrary vices. We are selfish, naturally possessive, tyrannical.

Man is not capable of extremes - he cannot understand if he reads too fast or too slowly, cannot see if there is too much light or too little, is thought mad if he has too much intelligence or if he has too little. Similarly, in nature, he is a mediocre creature poised between the infinitely great and the infinitely small - his life a brief space with an eternity on either side of it, himself a petty creature incapable of understanding the vastness of the universe but equally incapable of entering into the world of the infinitely small. Indeed Pensée No. 72 is one of the most powerful and most terrifying expressions of Pascal's view of the human state.

Human society is a reflection of human nature, founded not on reason, but on folly, custom and force. The principle of hereditary succession, for example, is absurd. Society rests not on justice, but on force - but this is, in fact, inevitable, since we have no means of knowing what justice is, and conceptions of justice and laws vary from country to country. For Pascal is fond of developing the paradox that however, foolish, unjust, and irrational society may be, it is better than if it were rationally organised: the madness of society is, in fact, a kind of sanity. Approval or disapproval of social usages varies with the degree of intelligence of the observer: the common people accept what is, though for the wrong reasons; the more intelligent denounce it; the really intelligent understand that it is for the best. Thus extremes meet; ignorance and the highest intelligence agree.

Various social usages are examined and, although at first sight irrational, shown to be useful. The principle of hereditary succession, though absurd, is a means of avoiding disputes and civil war.

Pascal, it is clear, is no revolutionary. Society is based on folly and injustice, but, given the nature of man, it must be. We do not know what justice is, and, if might and custom did not impose some sort of order, we would be fighting one another incessantly. Society must be accepted, both for practical reasons and because it is the will of God. It seems that, during the Fronde, Pascal steadfastly supported the government against the rebels.

The state of man, in short, is not a happy one. We instinctively desire happiness, but never achieve it. Man is also great, his very "misery" is a sign of his greatness. Inanimate objects and animals have no feelings; man alone is wretched, a sign sign that he is a "dispensable king".

There are several signs of human greatness. The sense of deprivation and loss, the instinctive desire for happiness and certainty is one. Man is great because he can turn his vices into virtues, and because he has a soul - without something immaterial within us we should not feel pleasure or have the power of subduing our passions. The desire for the esteem of others shows how much we instinctively prize the human soul: animals do not admire one another. Above all, man is great because he has the faculty of reason. Reason is our master, and if we disobey, we have the penalty of being foolish. Thought is the characteristic quality, the distinctive mark of man.

Man is thus a paradoxical creature, great and wretched, in whom the reason and the passions are ever at war, akin both to the angels and to the beasts. The best evidence of this paradox, of this fallen nature of man, is the need for "diversion", the subject of some of Pascal's most striking pensées. Man is great because he has the power of thought; but if, in his fallen state, he thinks, he is conscious of his wretchedness. He therefore turns to frivolous games and pursuits to occupy himself in order to avoid boredom, melancholy and depression.

Like all great writers, Pascal transcends his period, but he is of it. He is of it in his views on honesty and on style and, more important, by the great part played by the study of human nature in his apology. He is of it in the stress he lays on the restlessness and inconstancy of human nature, and the fickleness of fortune. He is of it in his Pyrrhonism and his Fideism, in his acute consciousness of the unreliability and the limitations of the human reason. He is of it, finally, in his love of paradox.

Paradox plays an important part in Pascal's Pensées. Not only does he delight in pointing out particular paradoxes of human nature and behaviour, but the paradox of human nature, the "grandeur" and the "misery" of man, is at the very heart of his apology. Moreover, the test of truth itself for Pascal is that it should be paradoxical, that it should reconcile apparently irreconcilable antinomies. Man is great; man is wretched: Christianity alone provides the solution which takes both these contradictory truths into account and shows that man has fallen from Grace. Pascal, indeed, states this as a principle. For Pascal, as we have seen, all men are right from their point of view; error consists, not in being wrong, but in seeing only one aspect of truth. This sense of the complexity of truth is, perhaps, one of the most rewarding aspects of the Pensées.

In his insistence that truth lies in the reconciliation of antinomies, Pascal has been seen as the ancestor of Hegel (thesis-antithesis-synthesis) and the dialectical materialists. He is also - in his rejection of metaphysics in favour of the study of human existence, and in his sense of the impotence of the reason, of the irrationality of society, of the futility of life as it is usually lived, and of the imminence of death - a forerunner of existentialism. But it is not merely for his historical interest that Pascal is read, but for his stimulating and provocative ideas, his original investigation into the nature of belief and the art of persuasion, and his searching analysis of the human condition, even if his portrayal and depiction of man is slightly pessimistic. The clarity of Pascal's vision strips reality of the protective veils in which our complacency swathes it, and sheds an unfamiliar and disturbing light upon it; sham and pretence disappear, and we see ourselves, our role and our place in the universe as they are. Reading Pascal is a chastening but a salutary experience, which sets things in their true perspective.