Why Buddhism Gets up the Pope's Nose (serious article with a funny name)
and Catholic Encyclopedia article on Buddhism (surprisingly rude, really)
The major criticism seems to be on two points; Buddhism lacks a concept of God and Buddhism is essentially negative about the world, the body etc. The former point we can readily concede, although seeing it as a virtue rather than a defect of Buddhist thought (perhaps the topic of another post.) The latter, Buddhism's supposed negativity, deserves some rebuttal.
This is not a criticism limited to the Catholics, either. Many who are in partial sympathy with Buddhist ideas voice similar objections. For instance, on a web-site called "A Call for a New Buddhism" we find the following;
1) Life is suffering. Is human life essentially painful from the moment of birth to the moment of death? Even ordinary life can be full of fun, adventure, friends, romance, good food, music and art. In many ways Buddhism has become an anti-life religion that appeals to those who always see the glass half empty rather than half full. Why should we deny the fact that life can be an enjoyable adventure and not just a pitiful veil of tears?I've also encountered variants of this objection phrased as a question many times when giving talks. (On one occassion someone asks why Buddhists only talk about suffering and I couldn't resist replying that that isn't true, we also talk about grief, pain, lamentation, misery and despair)
The objection comes primarily from a reading of the First Noble Truth (in translation) as "Life is suffering." Part of the problem is that old bug-bear, translation. I've said it before, and I'll no doubt say it again, languages are not perfectly isomorphic. Pali does not completely map into English on a word for word basis. The Pali word translated as "suffering" is "dukkha" which is much broader than the English word. In some contexts, suffering works well enough but the problem comes when we encounter the teaching that all conditioned experience is dukkha and translate that as suffering. A poke in the eye with a sharp stick is both suffering and dukkha. A delicious slice of rhubarb pie is dukkha but it certainly isn't suffering.
So what exactly is dukkha then? It is a universal characteristic of all conditioned phenomena experienced with the physical senses or the mind. It points to that aspect shared by all such experience as being imperfect, unsatisfactory, in some way incomplete or provisional. Some experiences can give us joy, but no experience can be completely sufficient. There is never enough rhubarb pie.
From the subjective side, this is the root of desire. The mind always seeks to fulfill itself, to complete itself, through objects. These objects can never give total satisfaction, so the mind always moves on to another desire. This is the endless, and ultimately fruitless, project of samsaric existence.
Far from seeing the world as an endless veil of misery, Buddhism teaches that this human existence is a balance of pleasure and pain. Actually, most of our mind-moments are neither, they fall in the neutral range of equanimity. Buddhism also teaches that other realms of existence, devas and brahmas, experience much more pleasure than pain, but are still included within samsara. So samsaric existence is not necessarily suffering, but is always incomplete and in a deep sense futile.
Furthermore, Buddhism has the Third Truth, there is an end to dukkha. This is where Buddhism, far from being pessimistic, is radically more optimistic than other religions. For a Buddhist, the Christian heaven is still bound within samsara. Buddhism teaches that there is an Unconditioned, the Nibbana element, which is an alternative to conditioned existence. Nibbana (or Nirvana) has been grossly misunderstood by critics of Buddhism. This is understandable, because the Buddha refused to define it very clearly. Indeed, the implication of Majjhima 72 is that is essentially indefinable (words and logic being conditioned cannot contain the unconditioned). The implication of this sutta is to reject the view of Nibbana as either a super-sensuous heaven or a state of annihilation (the two erroneous views often encountered)
Finally, it should be noted that far from rejecting this human existence and body, Buddhism teaches the "preciousness of human rebirth" since a human existence is rare in the world and is the optimum position from which to attain awakening. (Humans may not seem rare, but consider that there are more beings in a bucketful of garden earth than there are human beings on earth.)
So we have to conclude that Buddhism is not pessimistic. In it's appraisal of this life it is simply realistic, and in it's soteriological aspect is in fact extraordinarily optimistic.