Why believe in moral absolutes, or universal truths? I believe that what is true depends on your circumstances and who you are. Beauty is in the eye of the beholder. The same goes for truth.

It is difficult to be a consistent relativist – someone who does not believe in absolutes. To quote Peter Kreeft: "Relativism says there are no absolutes. Absolutely no absolutes. Absolutism says there are some absolutes. At least one absolute." If you are going to claim there are no universal truths, you cannot make that into a universal truth without destroying your own position. That is not a verbal trick, it is simply logic. Therefore it would be safer to be not a relativist but a "sceptic" – in other words, to admit that there might be a universal truth but to be unconvinced that anyone has ever found out what it is. But if you are to be an open-minded sceptic, you have to remain open to consider arguments from those who believe they have found it.

The trouble is that very few of us are willing to sit and really listen to those arguments. Most of us have actually made up our minds long ago. And often it is a case of not wanting to consider a particular argument because "I don't want to go there!" I don't want to have to be among those people who believe THAT. I don't want to find I am not allowed to do THIS (whatever it is).

As for beauty, clearly tastes differ, but there are also some common factors uniting things that are regarded as beautiful across all cultures. Sunsets and mountains and oceans tend to be perceived as beautiful by everyone, even if mood and taste and culture can help shape our responses. In the area of morality, despite all the variations between the customs and traditions of different human societies, kindness, courage, gentleness, integrity and honesty are always valued more than their opposites. These underlying constants are an indication that "universals" do exist, even if they cannot always be very clearly defined, and even if they take different forms in different times and places.

It may be that your relativism is based on the true perception that much of what passes for absolute is in fact conditional. But you need to carry on thinking it through. If you are right, it may still be the case that there are gradations of truth and untruth, goodness and badness; and if there is a gradient, there is a direction (up and down). We may never attain the absolute truth, but if one thing is truer than another it at least points in the direction of an absolute. The word "transcendent" is often used to describe the Absolute precisely because we never actually reach it.

Is it morally right to kill someone who is about to, say, detonate a bomb that will kill thousands of people?

Am I permitted to do something wrong if it will bring about something good? What if my only choices are evil, and all I can do is choose the lesser evil in order to avoid a worse? These are the kinds of questions that come up all the time in the moral life.

In reality, when we are faced with a choice of two evils, there is nearly always a third option – we just haven't thought of it yet. So the first thing is not to get trapped by the dilemma, but respond creatively.

But what if there seems to be no third way? A lot depends on the circumstances. Are you sure that the person isn't bluffing, and really will do the deed – and also that it will have those results you fear? (If you act on the basis of a wrong judgment it will be you that is responsible for a death.) Are you a policeman, or a soldier, or are you acting on your own (again, an awesome responsibility)?

Martin Luther King once said: 'the end is preexistent in the means, and ultimately destructive means cannot bring about constructive ends.' He also said, 'We will never have peace in the world until men everywhere recognize that ends are not cut off from the means, because the means represent the ideal in the making, and the end in process. Ultimately you can't reach good ends through evil means, because the means represent the seed and the end represents the tree.'

The Catholic Church also says that means and ends must cohere. The end does not justify the means (Catechism, para 1753). If we do a bad act, even if it is only to achieve something good, and even if the alternative is for something terrible to happen, then that bad act, while it may succeed in averting the thing we were trying to avoid, will engender something as bad or worse further down the line, because evil leads to evil. Doing something bad with a good intention does not make it good. (For the morality of human acts, see Catechism, paras 1749-56.)

Of course, things often don't seem so clear-cut in reality. Should I tell a 'white lie' to the Nazis who are hunting down my children, in order to send them off in the wrong direction? Most people would say yes – if only a lie would suffice to mislead them. It would certainly be a small sin, and one that almost anyone would excuse or even condone. That is to say, the 'subjective' guilt involved is minimal, because of the intention and the circumstances. One could also argue that the Nazis had no right to the truth in this case. Difficult cases like this, where two principles come into conflict with each other, do not make the principles themselves any less true or important.

If someone who is a not a Christian asks why we think Wicca is a bad religion, how should we answer them?

First of all, a lot depends on who is asking and why. Sometimes people who ask a question are not really wanting to know the answer, but just trying to be provocative. An answer should always be pitched, as far as possible, at the person who is asking. The first principle of any serious dialogue is to respect the person you are speaking to. That doesn't mean you need to respect his or her opinions, or agree with his or her beliefs. But you have to respect the other as someone who has a right to form opinions and hold beliefs.

Wicca is an attempt to revive a form of paganism that worships Nature, often as a Goddess. (This is not the same as 'Satanism', which involves a deliberate attempt to invert Christianity.) Wicca is wrong for all sorts of reasons. For one thing, nature is not all good, or loving. If you worship nature, you are usually worshipping Power, or Energy, or the Life-force (or Sex) – but not Love. But only Love is worthy of human worship. Secondly, it is just not TRUE. Nature is not God. Nature needs a Creator. That is the God we worship.

[For more on Wicca, click here.]

How do we know that the Devil and the other evil spirits won't ever repent and become good again?

Our Lord speaks of an eternal fire that was prepared for the devil and his angels (Matt. 25:41). The Church rejects the idea that evil will ever 'wear out' or get tired, and that the Devil will just give up the fight. Most Catholic theologians are agreed that just as the decision of men for or against God becomes definitive (final) in the moment of their death, so the decision of the Devil becomes definitive in the moment that he falls, because the relationship of the angels to time is different from ours. As humans living in time, our decisions and acts of will are all spread out, as it were, along a timeline. Those of an angel are concentrated into a point: or at least that is one way of understanding it. But more than that it isn't possible to say. Scripture is not much help, because it concerns us and our fate more than it does that of the angels (or animals). Some of the Church fathers, especially Eastern fathers such as Isaac the Syrian, thought that the devils might be saved in some way, but that seems to be against the mainstream view.

We know that God doesn't want anyone to go to hell. Given that Jesus gave his life to save everyone, and that there are always holy people praying for sinners and making reparation for them, could hell turn out to be empty in the end?

See the separate article on this point: The Problem of Hell

Why don't animals have souls? Will they be in heaven, or not?

According to St Thomas Aquinas, animals do have souls, as do plants, although he didn't think they would be in heaven (or the resurrected earth). A soul is what animates or makes alive. But every type of creature has its own type of soul, so animals have animal souls, which – in all the animals we know, except the human – does not seem to include faculties beyond those of instinct and feeling. I said 'seem' because we don't necessarily know for sure, and whatever St Thomas says, some creatures, such as the great apes in particular, and maybe dolphins and elephants, not to mention dogs, may have more to them than meets the eye.

Human souls are immortal because we have an ability (through our intelligence or reason) to 'step back' from the world as it appears to our senses, to reflect upon it and choose alternative courses of action, to judge what is true and false, and above all, to recognize and worship God. We are capable of a personal relationship with our Maker, and it is this which makes physical death to be not the end for us.

C.S. Lewis thought that animals could enter the immortal state and be found in heaven by virtue of their relationship with human beings, which in some way 'personalizes' them (in the case of pets, especially). So they come to heaven through us. His friend Charles Williams seemed to suggest (The Place of the Lion) that while individual animals may not be able to transcend the physical state, the species to which they belong are more 'real' than they are, and these are eternal archetypes which we will meet in heaven. So all individual lions, or all individual dogs, or mice, are fragments and glimpses of some great Lion-Angel, or Dog-Angel, or Mouse-Angel. Either way, we should not fear that animals we have loved and lost will not be found again in the place where 'every tear is wiped away' (Rev. 21:4).

The Bible is directed at human beings, and is mainly about them, so we cannot tell much about the fate of animals from reading it. We are free to speculate, as long as we do not lose the important distinction that makes human beings special: our direct relationship with God, not as a species, but as a unique person.

What if we discover dolphins can think, and what about life on other planets?

If dolphins could think in something like the way we do, they would be rational beings with immortal souls. The same goes for creatures (if there are any) on other planets.

I've recently discovered Neoplatonism. It seems like a beautiful philosophy to me, and it is a lot easier to accept than Christianity, because you don't have to believe things on faith that don't make any sense, like 'Jesus is God'.

If you like Neoplatonism, you should know that its key insights were incorporated into Christian theology long ago by Origen, St Augustine, Boethius, Denys the Areopagite, St Thomas and many of the great medieval thinkers. Most of these Christian writers thought that ancient philosophers like Plato and Socrates would enter eternal life alongside the Old Testament prophets who also died before Christ was born.

The reason Neoplatonist philosophers like Plotinus and Proclus rejected Christianity was because they were not prepared to accept the existence of a new source of information, beyond what is revealed in nature and reason, namely the 'knowledge of the heart' that we call faith. St Paul knew that the Incarnation would seem like 'folly' to the Greeks. You can't believe in the Gospel unless you are willing to accept the gift of faith.

But as to whether 'Jesus is God' makes sense, that is something that you have to look into some more: don't dismiss it too quickly, without finding out what it really means. The doctrine actually hinges on the meaning of 'person'. Jesus is a human being but a divine Person. To go deeper into this question of the Trinity (which is just another way of saying that 'God is love') see Bruno Forte's piece God the Trinity in our Archive section.

If we are wanting to get married to someone, what's wrong with having sex with them, to make sure you are compatible with that person before you take the plunge?

Because it won't actually give you the information you want. Having sex with someone before making a total commitment to them is totally different to having sex after making that commitment. The physical act may look the same, but there is a different relationship established by the vow, and you can't try that out beforehand.

It is worth saving yourself – and your virginity – for the one you marry because it is a gift you can really only give once, and by giving it to one person in the context of a marriage vow you make a much deeper and more solid union with that person than you could do otherwise. If you really love him or her, you will want to make it that kind of union, and you will be sad if you have to settle for anything less. The more you 'spread yourself around', the less 'whole' is the self that you can give to someone you love.

But what if it is too late, and I have slept around already, maybe because I made lots of mistakes about people, and now I want to get married?

Well, you can still give yourself, along with all your experiences and regrets, to the other person, but there will most likely be sadness involved. You can get through that, because love forgives and forgets, and God heals, but that doesn't mean it wasn't a mistake in the first place to do those things. It is like what goes on in the rest of our lives: we repent of our sins, and we even learn from them, so that good can be brought from evil, but it doesn't cease to be evil for all that: we never know what would have happened, and how much better life would have been like, if we had behaved differently.

Why marry someone at all?

Most of what people call 'marriage' is not what Christianity means by the word; it is more a kind of contractual arrangement between two people to live together for a period of time. What Christian marriage means (according to the Catholic Church) is not a contract but a covenant, by which two people become one. This is a very special kind of unity, which the Church believes all lovers deep down really want, but which is only possible to achieve by merging two lives into one through a binding promise that even the Church does not have the power to dissolve. Therefore it can only be done with one person, at least until that person dies.

Now you don't have to accept the Christian doctrine if you are not a Catholic, but it is important to realize that the Church puts it forward not as a way of restricting and frustrating people, but for the very opposite reason: in order to make possible a kind of personal fulfillment in love – and, by the way, a kind of secure framework for having and bringing up children – that no other arrangement allows.

Given the biological pressure inside us, if we aren't supposed to sleep with anyone before we marry, why shouldn't we masturbate? Surely it is just a physical thing, like sneezing, or scratching.

Not quite. If it were just that, then there would be nothing wrong with it, of course. And the Church does teach that the sinfulness of masturbation is much less than that of many other things, and may be reduced by emotional and physical factors, like the kind of pressure you mention, or the force of habit (see Catechism section 2352). But the pressure is made greater and more obsessive by giving in instead of struggling against it. Also, human beings are not just machines, or even animals. There is an added spiritual dimension, so that what goes on invisibly is more important than the visible. In the case of sex, the images we generate in our imagination, or dwell upon in our memory, are highly charged and deeply embedded in our soul. The human imagination is actually an organ of perception, and sexual fantasies can clog and obscure that perception. In the Sermon on the Mount Jesus says that the 'pure in heart' are blessed because they will see God. We can't 'see' God except by being pure, that is, focused, undistracted, 'one-pointed' (to use a Buddhist expression). Sexual fantasy is a powerful distractor. People used to say that masturbation 'makes you go blind': of course it doesn't make you go blind physically, but maybe the origin of this expression was the knowledge that there is a kind of spiritual blindness that it helps to create.

In Star Wars the Jedi apprentice is told, 'Your focus determines your reality'. There is a lot of truth in that. By focusing our attention and inner energies on the physical, or the sexual, aspect of ourselves we determine the level of reality that we are going to be living and operating on. On the other hand, we can raise that level through a struggle for purity. Energies that were going into sex are used in other ways.

Isn't that just repression of our feelings? It isn't healthy to bottle them up inside. It can't be good to fear them and hate some part of yourself.

No it isn't. Sublimation is different from repression. The point is not to bottle them up, but channel them in a different way. Those energies and feelings, those desires and pleasures, are good. The Church defined as 'heretics' those people who said the opposite (Gnostics, Cathars, etc.). The Puritans got it wrong too, later on. But it is not easy to sublimate, and many people take the much easier path of repression, and that leads them into deep trouble later on.

Prayer is the key. If we learn how to pray, we learn how to open ourselves up to the guidance of God even inside our psyche, where grace can flow in and help us. But we block grace in so many ways. We think we are praying when we really aren't. True prayer lets God in, but often we are afraid – or just shy – of being open to him, even though he made us. We try to keep him at a slight distance, or inside a little inner 'box' where he feels safe, and where we can open the lid and talk to him from time to time.

If a woman is pregnant because she has been raped, or if her life is at risk if he she has the baby, shouldn't she be allowed to have an abortion? Why does the Church say she shouldn't?

What the Church says is that if conception has occurred, then a new human life exists, which has to be taken into account even though (being still invisible and unknown) it may seem to us at the time much less important than the life of the woman who is pregnant. If there was a way, after being raped, of preventing conception occurring, then I don't think the Church would object, but most methods don't prevent conception, they prevent implantation after the egg and sperm have already united together into a new organism, so that the problem is simply 'flushed away'. You shouldn't flush away a human life.

The life of the child is separate from that of the father. It is not just an extension of him, but a new creation of God (even though God uses material from the father as well as the mother to bring it about). The woman may well feel the pregnancy resulting from rape like a kind of invasion of her body, but the child is not the rape, and should not be held responsible for it. It may even in a mysterious way help to redeem the rapist. When a raped woman gives birth, she is often quite capable then of seeing the baby for itself, and loving it. While it is in the womb she is likely to project her feelings about the rape on to it, but once it is born the reality and value of the child is more obvious.

As for whether abortions can ever be justified to save the life of the mother, this is a complicated issue, and for all the really technical discussion of the Church's position on abortion, stem cell research, cloning and suchlike, we would refer you to the Linacre Centre web-site. But one important principle to bear in mind is that you cannot (morally speaking) deliberately kill one person in order to save another, even if you may have to allow one person to die, or even sacrifice yourself so that another will live. These distinctions may seem trivial, but they are absolutely crucial for thinking rationally about situations where the life of one person is physically entangled with that of another, the way it is in the body of a mother.

Why does the Catholic Church oppose the use of condoms to prevent the spread of Aids?

Aids is transmitted through blood and semen. The Church cannot encourage the use of condoms, not because condoms are evil in themselves, nor because they might prevent the conception of a child, but because this would be seen as condoning the behaviour that leads to the disease being transmitted, namely promiscuous sex. Instead, official policy is to promote matrimonial fidelity and chastity as the best form of prevention.

It is of course true that if someone is already involved in prostitution or homosexual sex, or in any form of sexual activity outside marriage, all of which the Church says is wrong, then using a condom would not make things worse, and would at least minimize the risk of transmitting a deadly disease. The late Cardinal Basil Hume of Westminster stood by his assistant bishop, Victor Guazzelli, when he said: "it seems to me that if people are set on intercourse they at least have an obligation of not passing on disease and death, even if the only possible means to them is the use of a condom. This seems to me common sense."

However, it is unlikely that anyone who is prepared to disobey the Church's teaching by having promiscuous sex is going to be one of those who refrain from using a condom just because the Church tells him to! And the use of the word 'him' here reminds us that we are talking mainly about male behaviour; because another point about contraception in general is that it is custom made for the exploitation of women by men, who tend to want as much sex as possible while minimizing the risk of inconvenient pregnancies. What we need to do is change the pattern of male behaviour.

Condoms are not 100% effective in preventing the transmission of HIV/AIDS and STDs. That implies that the more they are used the greater the chance that something will be transmitted. The fact that everyone pins so much hope on them is a symptom of our modern obsession with technocratic solutions to every problem. The big pharmaceutical companies and other vested interests, which control the advertising and manipulate a lot of the media coverage of this issue to their advantage, exploit this. But surveys in Uganda and Philippines, compared to Thailand, show that where serious chastity education programmes are in place, AIDS can be reduced more effectively than by the mere distribution of condoms.

So much of AIDS talk implies that human problems are reducible to material and mechanistic terms, thus implicitly denying the spirit, the person, human freedom and thus the very roots of morality. Instruction in the use of contraception – in theory as well as actual practice – is worlds apart from the education of the heart required for chastity and abstinence.

Why don't Christians believe in reincarnation?

Belief in reincarnation is growing in Europe as faith in the Church's teaching declines. Some people even claim to have "memories" of previous lives. Without disputing the fact of such experiences, one might still ask why people suppose that they are flashbacks to "my" previous life rather than someone else's? Maybe memories can be shared or transmitted. The real issue is one of interpretation, and of the desire to believe a doctrine that at first sight appears fairer, more reasonable, than that of the Church. Why can we not be granted a second or third chance at spiritual happiness? Why can we not "stay in school" for as long as we still need to learn, moving from one body to another until we don't need bodily experience?

One answer is that such further chances would precisely not concern "us" at all. Christianity is often accused of being concerned less with this life than with the life of a world to come. In fact the opposite is the case. It is not really concerned with the education and liberation of the soul, but with the saving of the body-and-soul together – in other words with the saving of this particular life. The experiences, feelings and decisions of my life are to be redeemed and transformed in eternity. They are not merely a series of occasions for a detachable "soul" to learn its lesson and move on.

Philosophers have come up with many ways of defining personal identity. If "I" am just the continuity of my memories, someone who remembers a past life is by definition remembering his own previous existence. Christianity teaches a more subtle doctrine: the preciousness and unique value of each life, which has a unity of its own when viewed in relation to the God who created it and calls it to himself. It is this which constitutes my real "personal identity", and it is this which Christ died to save from death.

It is, however, very important to prove that this doctrine is not "unfair" to those who die prematurely, or who commit sins of which they would have repented had they been given more time to learn from their mistakes. Christians believe that in the moment of death, when we are removed forcibly from time, God will be revealed to us. In that revelation, there must surely be a series of stages. Before we are able to see God face-to-face, most of us will go through a stage of discovery and suffering known as Purgatory. Into this stage (which cannot be measured in time, because it is outside time as we know it) we can imagine concentrated all the lessons and "second chances" that we could wish for even if we had a thousand lifetimes. There is no need to go through the whole process of conception and birth and upbringing over again, in order to receive that healing and that instruction.