John Kilcullen
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The term “philosophy” can be used in various senses. Here I mean by "philosophy" the practice of reflecting seriously on what I believe about the questions I regard as the most fundamental, to make sure as far as possible that what I believe is actually true. There is a second sense of the word, in which “a philosophy” is a set of beliefs or opinions or conclusions about certain important questions, but philosophy in the sense I am concerned with is the practice or habit of reflecting on beliefs, and not a particular set of beliefs.
Part of reflecting seriously on what I believe about the most fundamental questions is to consider whether these really are the most fundamental questions. Maybe there are other questions I should be thinking about as well as, or instead of, the questions I currently regard as fundamental. Philosophy therefore includes serious reflection on the question, What are the most fundamental questions?
I can be mistaken in thinking that I believe something. There may some verbal formula I recite on certain occasions but do not really and seriously believe. One sign of serious belief is concern to be clear about what the formula means. Another is concern that the belief be true. If someone subscribes to some formula but does not take much time or trouble to understand its meaning or to consider the reasons for and against believing it, then it may be that the “belief” is just “lip service”. My aim should be: to make sure that what I really believe about the questions I really regard as most fundamental is actually true.
Philosophers have sometimes said that it is somehow wrong to believe something without proof or without evidence. This is not my opinion. If, when I reflect on something I believe, I find that I do not know why I believe it, that is not in itself a reason for trying not to believe it. (I say "trying", because belief is not directly a matter of choice: I can choose to reflect on the truth of something I believe, and this reflection may in the end lead to a change of opinion, but I cannot directly choose what opinion to believe.) Even if I have good reasons for my belief, it may take much thought before I can formulate and express those reasons. For some really fundamental beliefs no reasons can be given, because there are no more fundamental beliefs that could serve as reasons--in such a case reflecting on the truth of the belief may be a matter of testing it by considering objections against it, for example by considering whether I can accept all the things it implies. "Justify this belief (right now!) or abandon it" is not a reasonable demand. See my essay, "The Ethics of Belief".
So philosophy is the practice of asking (1) what are the most fundamental questions that need answering, (2) what do I believe (reallybelieve) are the answers to those questions, (3) are those answers correct or do I need to revise them, and (4) is my list of the most fundamental questions adequate or should it be revised?[Note 1]
It seems obvious that this is something everyone should do. Some people make a profession of it (they are professional “philosophers”), but everyone does do it to some extent, and most people should do it more than they do. We owe this to our neighbours. Our opinions on the questions we regard as most fundamental shape our actions, often with impact on the people around us. They have a right to expect us to take a reasonable amount of trouble to make sure that the opinions we are acting on are true. To engage in a reasonable amount of philosophical reflection is a civic duty.
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There is not necessarily any opposition or conflict between religious belief and the practice of philosophy. Many Christian and Muslim thinkers have been philosophers as well as theologians. A religion is “a philosophy” in the sense explained above, i.e. in the sense of a set of answers to the most fundamental questions. People are often converted or recruited to a religion as a result of reflection on these questions, i.e. as a result of philosophy in the sense of a practice of reflection. Philosophy in that sense is part of religious thinking, for example in clarifying the meaning of formulations of religious belief, in explaining why one should believe, in resolving objections and difficulties.
A religion and philosophy will come into conflict only if reflection leads to the conclusion that beliefs essential to the religion are not true. Most religious believers believe that their religion will be vindicated by inquiry into its truth--they do not fear, but encourage, reflection, at least in the appropriate circumstances. “Appropriate circumstances” may mean: if the inquirer is intelligent and well informed and able to consult expert exponents of the religion, and able and willing to spend a reasonable amount of time on the inquiry.
Augustine: Some religious thinkers have reflected in a philosophical way on the relationship between philosophical reflection and religious belief. For example, Augustine has quite a lot to say on this subject. According to Augustine there are two guides, "authority" and "reason". (For example, if your teacher suggests you read a certain book, and you do so, you are being guided by the teacher's authority--perhaps "credibility" would be a better word--to read the book, but you then discover for yourself--this is "reason"--whether what the book contains is helpful.) Augustine often says that authority comes first, assuming that children spontaneously accept the guidance of the adults around them; later, the person thus guided may come to see the reasons behind the teaching. Augustine has in mind not only theoretical matters, but also, and especially, learning how to live:
We are guided in a twofold way, by authority and by reason. In time, authority has the prior place; in matter, reason.... To those desiring to learn the great and hidden good it is authority which opens the door. And whoever enters by it and, leaving doubt behind, follows the precepts for a truly good life, and has been made receptive to teaching by them, will at length learn how pre-eminently reasonable those things are which he pursued before he saw their reason, and what that reason itself is... (De ordine II.ix.26).Children at first trust unreflectively, but as people mature they begin to consider whether there are good reasons for trusting:
Authority demands of us faith, and prepares man for reason... although authority does not leave reason wholly out of sight, when the question of who may be believed is being considered (De vera rel. 24, 45)God does not demand blind belief:
God forbid that we should think that He hates in us that in which He has created us superior to the other animals. God forbid, I say, that we should believe there to be no need to accept or to seek a reason for what we believe, since it would not even be possible to believe if we had not rational souls. In certain matters pertaining to the doctrine of salvation, which we cannot yet understand but which some day we shall be able to understand, it is right that faith should precede reason. Faith thus purifies the heart, rendering it capable of receiving and enduring the great light of reason, Thus it is reason itself speaking by the mouth of the prophet when he says: "If you will not believe, you shall not understand"...... If, then, it is reasonable that faith precede reason to attain to certain great truths which cannot yet be understood, it is without doubt true that it is reason, in however small degree, that persuades us to it, so that reason itself precedes faith. It is on this account that the Apostle St. Peter admonishes us to be "ready always to satisfy everyone that asks you for a reason of that hope which is in you" (1 Peter 3:15) (Augustine, Letter 120, i, 3, 40)In Augustine's view, "faith" is not an unaccountable, blind conviction based on feeling of some sort. Faith is belief based on credible authority, i.e.on the word of someone I have reason to trust--I believe something I can't verify for myself because some person I have reason to regard as trustworthy tells me it is true. Faith in this sense is essential to life. If I want to go to some place I've never been to before, I need advice from someone I have reason to believe knows how to get there. Once I've got there, I will know for myself how to get there, but before getting there I don't know, I have to trust. As children we spontaneously trust our parents and other adults, as adults (having discovering that people are not always trustworthy) we trust people we have reason to regard as trustworthy, and by following advice (if it is good advice) we may come to a position where we know for ourselves.
Muslim thinkers also reflected seriously on the relationship between philosophical reflection and religious belief. During the middle ages, European Christians learned a great deal from Muslim philosophers and theologians, who had already made an intense study of the philosophies of Aristotle and Plato and had noted the many points at which Greek philosophy came into conflict with religious belief. See Oliver Leaman, An Introduction to Classical Islamic Philosophy.
...the views of [Greek] philosophers were condemned on occasion as heretical and beyond the limits of Muslim belief. ... But in rejecting philosophy the theologians were not rejecting reason; on the contrary, they were enthusiastic concerning the value of reason when employed in a suitably domesticated context. It is not difficult to find Qur'ānic backing for this position. The Qur'ān does not require that people believe in its teaching blindly. Both believers and unbelievers are invited to ponder, reflect and understand through the use of their reason. It warns against blind obedience to one's predecessors (II, 170; V, 104) and repeatedly addresses itself to the understanding of its audience (III, 65; XII, 2). Although the teachings of the Qur'ān are based upon divine authority, they often seek by rational persuasion to bring about faith. There are a number of verses which seek to prove that God must be a unity, in particular the verse which argues that the whole universe would have perished if there existed several gods beside God (XXI, 22). Similarly, the Qur'ān seeks to establish by argument the veracity of the prophet, referring to the pious life which he led prior to revelation (X,17) (Leaman, pp. 14-15).
For some of the discussion among Muslims of Greek philosophy, see my lectures here and here. Al Ghazali, one of the critics of philosophy, wrote a short account of his intellectual quest, entitled "The Deliverance".
For an outline of several medieval views of the relationship between philosophy and religion, see E. Gilson, Reason and Revelation in the Middle Ages.
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A religion always, or at least usually, has its recognized guides or teachers. Non-religious groups (e.g. political movements) often have recognized expert opinion leaders. The leaders of religious and other groups often encourage young people and other newcomers to the religion or movement to be guided by the teachings of these leaders.
A teacher’s claims should be tested. It is unwise to accept guidance from just anyone who offers advice. We can get advice about which guides are worth following, but the people who offer this advice may not be good guides. People seeking guidance must test the guides by asking them questions and considering what others say about the matter – i.e. the people seeking guidance must also think for themselves.
Some advice from me:
(1) Don’t try to abdicate or renounce your own judgment or current opinions—you have to judge, making use of your present opinions, whether what the teacher says makes sense and whether the teacher is likely to know the truth.
(2) Don’t conceal from the teacher your own opinions or your reactions to what the teacher says—if the teacher is a good guide, he or she needs to know where you are at. If the teacher is not a good guide, you will find that out more quickly by seeing how they deal with your reactions to what they say.
(3) But don’t cause unnecessary offence. Don’t say, “Surely you don’t mean…”, rather, “I’m not sure I understand—do you mean…? Or do you mean….?" (Help sort out the puzzle.) Don’t say, “But that obviously conflicts with…”, rather, “I don’t see how that fits with…”
(4) If the teacher says that there is no time to deal with your question at present, or that it will become clearer later, then accept that for the time being (it may quite well be true). But keep your question in mind for later. If the teacher never gets round to it, continually postpones it, eventually gives an answer but it makes no sense (even when you have politely suggested possible meanings), these are bad signs. If the teacher seems to discourage questions and politely expressed objections, or suggests that you are stupid or ignorant or hostile (and you are not), or treats you as a troublemaker or the class joker, these are also bad signs. On the other hand, considerable patience on your part may be appropriate; some subjects are very involved and complicated.
(5) You will never become quite certain that the teacher is a good guide, or the opposite. The real question is whether it seems worth your while to continue to listen to this person, or whether the time has come to try some other guide. It is also reasonable to listen at the same time to advice from several different people who disagree with one another.
If at present your beliefs are those taught by some version of Christianity, then the following may be useful in reflecting on those beliefs.
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Christianity has been around for a long time, its literature is immense. No one can be sure that there is not somewhere some Christian teacher who has the answer to any given difficulty that can be raised against Christian beliefs, or whether there is some possible version of Christianity[Note 2] free from all objection. Some of the obvious questions and difficulties are as follows.
Like Jews and Muslims, Christians are monotheists, not polytheists, i.e. believe that there is only one God and not many gods. Unlike Jews and Muslims, however, Christians believe that God is three persons (the Father, the Son and the Holy Spirit), and that one of these divine persons became a human being (namely, Jesus Christ) and suffered death to save mankind (or at least some of mankind) from sins that otherwise would have led to eternal damnation in hell.
(1) How can there be one God and not three, if
What better evidence could there be of plurality than that one is not the other?[Note 3]
(2) If God is eternal, immortal and impassible (as all who believe in God believe), but Christ suffered and died (really died, not just seemed to die), then how can Christ be God? Christians do not believe that Christ is two persons, one immortal and the other mortal: they believe that in Christ two natures are somehow united in one person--the same person is both mortal and immortal. This seems contradictory, implying that during the three days between the crucifixion and the resurrection Jesus Christ was both immortal and dead. (Compare: "in order to pay the debt of our condition, the inviolable nature was united to the passible, so that as the appropriate remedy for our ills, one and the same 'Mediator between God and man, the Man Christ Jesus,' might from one element be capable of dying and also from the other be incapable": the "Tome of Leo" adopted by the Council of Chalcedon, http://www.fordham.edu/halsall/basis/chalcedon.html.)
It may be said that there is no contradiction, since Christ is immortal "as God" or "according to his divine nature", and mortal "as man" or "according to his human nature". But this does not remove the contradiction. If X and Y are incompatible, to say that some one individual is X "as W" and Y "as Z" simply shows that the same individual cannot be both W and Z.
(3) How does the death of Christ save anyone from anything?
One traditional answer to question (3) is that human beings have all sinned against God, that their sins deserve eternal punishment in hell, and that no human being can be reconciled with God and forgiven unless someone suffers on the sinner’s behalf; and the only person whose suffering could suffice to earn forgiveness for mankind is Jesus Christ, the Son of God. (This is the account given by Anselm.)
(4) Why is it that God cannot forgive sin unless someone suffers (indeed, dies) on account of the sin?
(5) How can another person's suffering win forgiveness for me?
A devotional focus on the detail of Christ’s sufferings (as for example in the movie "The Passion of the Christ") for some people prompts the reflection how much Christ loved us, if he was willing to undergo such suffering to save us from the punishment due to our sins—how much this tells us of Christ’s love for mankind. But on the other hand, what does it tell us about the Father, who apparently could not be reconciled with mankind except through such suffering? What sort of father requires the bloody death of his son before he can be reconciled to other children, from whom he has been estranged by the disobedience of their ancestor (Adam)? (See Romans 5:10, 8:32.)
The problem of evil: The existence of evil is a problem for any theism in which God is held to be both good and all-powerful. It is a problem for Christians particularly in connection with the doctrines of original sin, predestination and grace. Why did God permit Adam to sin? Why does he leave the mass of mankind, or for that matter anyone, to be damned eternally? Indeed, why does he permit any sin at all? And why does he permit pain and so many other physical evils? Many answers have been attempted to these questions. In some of these answers, there is a suggestion that we should accept suffering (for ourselves, or for some other person we hold dear), because it serves some good purpose (what that might be is explained by the answer). But will a father make use of (or allow, though he could prevent it) his children's suffering as a means to any purpose, however good? No one who allows a child of mine to suffer avoidably, even to advance some good purpose, is a friend of mine. See the article by Stanley Fish
Since the 16th century Christians have been divided into Protestants and Catholics. One of the fundamental differences of opinion in Reformation times was over the question, What is the source of authoritative answers on questions of Christian faith? Catholics said: The Church, Protestants said: The Bible. The Protestant slogan was “sola scriptura”, i.e. the Christian faith is determined by the scripture [Bible] alone. Catholics replied that not everything that God has revealed to the Church is recorded in the Bible, which therefore needs to be supplemented by Christian tradition; their slogan was “scripture and tradition”. Protestants held that every individual Christian must read the Bible and form his/her own judgment of its meaning (“private judgment”). They did not think that one interpretation is as good as any other, but that each person must form his/her faith directly from the Bible and not rely on the authority of any other human being. Catholics held that the correct interpretation of the Christian faith is that which is taught by the Catholic Church, so that individuals must defer to the judgment of the Church. Catholics held that the pope and Ecumenical Councils are authoritative interpreters of the teaching of the Catholic Church, so that (under certain circumstances) a Council or a Pope will be “infallible”, i.e. capable of giving an absolutely final decision as to the true answer to a question of religious doctrine.
Historians have traced the development of these doctrines. On the notion of heresy, see my essay "The medieval concept of heresy". According to Brian Tierney, Origins of Papal Infallibility 1150-1350: a Study on the Concepts of Infallibility, Sovereignty and Tradition in the Middle Ages (Leiden, 1972), the doctrine of papal infallibility defined by the first Vatican Council cannot be traced back earlier than the 13th century. According to this doctrine, God would intervene (if necessary by miracle) to stop a pope who was on the point of defining some heresy as Catholic doctrine. The 14th century theologian William of Ockham rejected the claim made by Marsilius of Padua (who on this point anticipated the later Protestants) that no one need believe anything but the Bible (see my essay "William of Ockham and Early Christianity"); but he denied that popes and councils are infallible. According to Ockham, God will intervene (if necessary by miracle) to prevent the last orthodox Catholic from assenting to a heresy being taught as Catholic doctrine: in other words, an heretical doctrine might be taught by pope and council and accepted almost throughout the Church, but God will make sure that there is at least one Catholic who speaks up for the truth. On Ockham’s view, doctrine taught by pope or council is not guaranteed to be true until it has been accepted by absolutely every member of the Church. (See my essay, Ockham and Infallibility.) Ockham’s position had few adherents during the middle ages, but more recently many theologians have held that papal teaching requires the consent of the Church. (Their position has been repudiated by Church officials.)
During the 17th century, especially in France, Protestants and Catholics debated “the rule of faith” and argued one another to a standstill. Catholics pointed out that the Bible did not come into the world as a single book bound into one volume with a clear message from God authenticating it as divine revelation. Rather, various writers produced many little books that were later collected together into one volume and acknowledged as revelation by the Christian community. There were a number of other books, apparently very similar to those accepted into the Bible, that the community rejected (the “apocrypha”). The list of accepted parts of the Bible is called “the canon", and the writings accepted are “canonical scripture”. The Catholic argument was that unless the Christian community, i.e. the Church, is authoritative, its list of the canonical scriptures has no authority and the collection of these scriptures, i.e. the Bible, has no authority. Further, the doctrine that the Bible contains no error is not itself found in the Bible (there are texts that suggest this doctrine, but they do not amount to proof). The inerrancy of the Bible is a traditional doctrine of the Church. “Sola scriptura” cannot be the rule of faith, since, if it were, Christians could not know what books belonged to the Bible and would not know that those books contain no error---only Church tradition can establish these fundamental points of doctrine.
On the other hand, the Protestants made a similar objection against the Catholic “rule of faith”. Just as it is difficult to know which books belong to the Bible, similarly it is difficult to know who belongs to the Church. A possible answer to this objection is provided by the idea that all Christians should be “in communion with” the pope and should accept the teachings of Ecumenical Councils. However, Catholics have always admitted that it is possible for a pope to become a heretic or to lose his faith (papal infallibility applies only to occasions on which a pope sets out to define Catholic doctrine---it is not always easy to recognize these occasions). As for Ecumenical Councils, it is sometimes difficult to know whether a meeting counts as an Ecumenical Council.
Catholics urged the difficulties of “private judgment”---how could an illiterate peasant decide the meaning of difficult passages of Scripture? How could such a person be sure that the text of Scripture had been properly edited and translated? On the other hand, Protestants argued that each Catholic, including the illiterate peasant, would have to decide by private judgment whether the Catholic Church’s claims to authority were well-founded. To accept the authority of the Church on the basis of the authority of the Church would be a circular argument.
Catholics held that the authority of the pope is superior to that of a council, but Protestants pointed out that the Council of Constance had deposed three rival claimants to the papacy (one of which would have been legitimate, though no one could tell which) and elected a new pope. Popes since Constance trace their "apostolic succession" through the pope appointed by that Council.
In recent times a third strand of opinion has emerged, often called “liberal”. Liberal Christians believe that Christians do not have, and do not need, any means of getting absolutely final and infallible answers to every doctrinal and moral question. Some liberal Christians believe that there is no permanent truth, but most believe that there is a true answer to fundamental questions but no certain way of getting the true answer. They hold that Christian believers should study the Bible and religious tradition and discuss their questions with other Christians, but should also consider other, non-Christian, sources of information and insight and hope to arrive at a conclusion which will not be final and infallible but only tentative and probable. There is no standard of "orthodoxy", certainly none that should be enforced.
Liberal Christianity may well be intellectually defensible, but it is questionable whether liberal Christians are really Christians. If non-Christians have turned out to be right in rejecting the claims to special knowledge of God’s truth that have been made by Christians since New Testament times, would it not be better to admit that they were right and join them, instead of adapting traditional language to express non-Christian ideas?
In opposition to theological liberalism there are people who call themselves Evangelicals (or simply “Christians”, with an emphasis that implies that those who disagree with them are not Christians). “Evangelical” Christians hold that the Bible is “infallible”, i.e. that once you know what a text in the Bible means, then you can be certain that that is the truth. This is a return to Reformation Protestantism and is open to the same objections. Evangelicals show no awareness that the “canon of scripture” is problematic: they act as if their Bible was handed down miraculously as a single volume bound up between its covers. They try to prove the infallibility of the Bible by quoting Bible texts (a circular argument), not realizing that there is any question whether the texts they quote are part of the Bible, or any question about which writings the assurances that might be given by such texts would extend to. They claim that their interpretation of the Bible is determined by the meaning of its words, but in fact their reading of the Bible is coloured by the doctrinal tradition of their sect.
My own position is closest to that of the Liberals, except that I am not a Christian. It seems to me that no man should be regarded as God, and no individual, body or book should be regarded as an infallible source of messages from God--such beliefs give divine authority to merely fallible and human opinions (which may be interesting, worth considering and even, often, true--but not unfailingly true). We should think for ourselves, giving serious consideration to the opinions of other people and accepting guidance (cautiously), but not regarding either oneself or anyone else as infallible.
Claims are often made for the superiority of Jesus’ moral teaching. Read the New Testament and then read some of the Greek classics of morality (e.g. Plato's Apology and Phaedo, the Meditations of Marcus Aurelius, the Discourses of Epictetus). Is the moral insight of the New Testament superior? Christianity has been a vehicle conveying a good deal of ancient Greek philosophical wisdom to modern times.
Christians have recently become outspoken opponents of capital punishment. However, through most of Christian history Christians made no objection to capital punishment. God himself, according to the orthodox tradition, punishes sinners in hell for all eternity, with a retributive punishment worse than the death penalty.
Concern for the poor and oppressed is common to Christians and non-Christians--it is not true that without the Bible and Christian tradition no-one would be concerned for the welfare of other people. It may be true that most charitable work done in countries like Australia is done by Christians; it is also true that most charitable work done in Muslim countries is done by religious Muslims. In a community in which moral seriousness is traditionally shown by active membership of religious organisations, it is no surprise that people whose moral seriousness is shown by altruistic work in the community also belong to religious organisations. Dedication to community work correlates with religious committment, but may not be caused by it. (For another discussion of this and other relevant questions see Jonathan Haidt, Moral Psychology and the Misunderstanding of Religion.)
There are a number of special moral doctrines insisted on by many Christians but ignored or rejected by many non-believers: e.g. condemnation of homosexuality, masturbation, pre-marital sex, contraception, abortion, IVF, stem cell research, etc. Some of these doctrines may be found in the Bible, but they are also supposed to be dictates of "Natural Law", which implies that it should be possible to justify them to a reasonable person, without reference to divine revelation. ("Natural law" is a Greek and Roman philosophical and legal concept; see my essay, "Natural Law"). Christians don't seem to have much success in formulating such reasons.
Religious believers sometimes claim that without belief in God there is no morality. For a recent example, see Michael Gerson, "What Atheists Can't Answer": "We should cultivate the better angels of our nature because the God we love and respect requires it." But obedience to someone we respect and love cannot be the absolute foundation of morality -- unless we already have moral values, how can we know whether God is worthy of love and respect, or that obedience is an appropriate expression of love and respect? If a person we respect requires something we judge to be immoral, does not this destroy or reduce our respect? If we suspect that God is a powerful but evil tyrant, we might obey out of fear, but not out of love and respect. In deciding whether to love or merely fear God, we must make use of moral conceptions we have independently of obedience to God. If we are supposed to be uncertain whether we should accept the constraints of morality, God cannot be the answer. See "Divine Command as the Foundation of Morality".
The meaning of life is no mystery. From ancient times, everyone who has thought seriously about the matter has concluded that the meaning of life consists in friendship (or "love" if you prefer the term). Christians believe that God has made it possible for human beings to live in friendship with God and in friendship with all God's children. But it is not true that without God life has no meaning. We still have human friends and care about them just as much.
See also Religion and Politics
Recently there have been a number of books attacking religion and faith and arguing against the existence of God. For a critique of these attacks see the article by Anthony Gottlieb in The New Yorker. In the opinion of some of the attackers, faith and reason (or "science") are simply incompatible. This is not my opinion. Sometimes it is rational to trust someone who offers guidance, sometimes it is not. The problem is to know when it is reasonable to have faith. See above.
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Note 1. As an academic discipline, philosophy is (like other disciplines) best defined sociologically, i.e. first we identify the group of people commonly regarded as philosophers, and then consider what activity or activities they engage in as members of that group. The philosophers are people found in philosophy departments, who read and contribute to certain journals, who read and write books reviewed in those journals and set as prescribed reading in philosophy courses, etc., and other people not in philosophy departments who read and write the same sort of thing; and philosophy in the professional sense is the collection of things those people do. Looking at the matter in this way, there is no reason to suppose that philosophy will be the same thing from age to age, or that all philosophers, even in the one generation, will all be doing the same thing or will all agree on what the subject includes, or that what they do will not also be found in other professions (e.g. physics). The alternative approach to defining a discipline can perhaps be called Platonic: we try to pick out some "idea" that defines the discipline, e.g. that philosophers are all concerned with "being". Such an approach does not seem to me to have had much success. The various academic disciplines are more like "conversations" that have branched off from an original conversation in which Socrates was at the centre.
Note 2.What counts as a version of Christianity? Christianity has been formulated in various ways, and it would be unreasonable to claim that only one formulation can count as Christianity. And over time, any of these formulations can be amended by deleting some bits and/or adding other things. There will thus be a "family resemblance" among the various versions, without any sharp line such that modification beyond that line produces something that can no longer properly be called Christianity. All the same, it does seem that some positions should be regarded as attempts to use traditional Christian language to say essentially non-Christian things, and not as legitimate versions of Christianity. There is no sharp line, but there is a vague region beyond which the family resemblance is lost.
Note 3. “The Planet Venus”, “The Morning Star” and “The Evening Star” are three names for the same planet. But “Father”, “Son” and “Holy Spirit” are not merely three names for the one thing. None of the three persons is identical with any of the others—the persons are “really distinct”. See Questions and Answers on the Trinity, question 30; See also Catechism of the Catholic Church, para. 254.