Weighing up the Arguments For and Against Christianity


In this piece I outline an approach to weighing up the degree of evidence in favour of Christianity with the degree of evidence against it. I discuss this approach in analogical terms as similar considering how much load (arguments against) can be borne by the legs of a table (arguments for), in order to support justified belief in a proposition (the table, or in this case belief in Christianity). Having outlined this framework, I then proceed to list the fourteen key pieces of evidence which I think are relevant, and whether I think they provide evidence for or against Christianity. I conclude by offering some personal reflections on my subjective sense as to how these different evidences balance out against each other.

Specifying the Question

Suppose that we agree to the following set of propositions:

  1. A creator God exists
  2. This God is omnipotent and omniscient
  3. This God desires to communicate his divine will to all mankind and aid everyone in entering into a willing relationship with him

Subject to minor rewording of 3 to rectify various possible quibbles, when I use the word ‘God’ henceforth in this piece, I mean a God that satisfies 1-3.

These three propositions, as I take it, represent approximately the limits of what the many philosophical arguments for the existence of God can establish (e.g. the cosmological argument, the moral argument, the teleological argument, the ontological argument, the transcendental argument, etc). What I aim to do here is presuppose the success of such arguments in establishing 1-3, and then consider the question as to which of the world’s revealed religions are genuine instances of divine communication with humanity which preserve (to a reasonable level of accuracy) divine teachings and intentions. In particular, I wish to consider (multi-part) proposition:

4. The life of Jesus of Nazareth (and the events surrounding it) was the supreme method by which God has revealed himself to humanity, and the teachings of Christianity accurately indicate God’s will for mankind.

Although not its strict logical negation, for our purposes here I wish to consider its counterpart as:

4′. Christianity is not uniquely divinely inspired (either not at all, or at least no more than many other religions), but instead developed over historical time as a result of the shifting and often   conflicting ideas, motivations, and opinions of many different individuals (i.e. like Christians would believe other religions developed).

Henceforth, when I talk about ‘Christianity being true’ (or similar), I am referring to the truth of 4. Rather than speaking of Christianity being false, I shall instead refer to the truth of 4′. I acknowledge that 4 and 4′ are not strictly speaking negations of one another, but for our purposes here I think they serve as the most useful propositions to juxtapose.

An Analogy: Supporting Legs and Heavy Bricks

The following analogy may help readers to understand the approach I take here. Being an analogy, it is of course imperfect, but hopefully it will nonetheless still be of use.

Consider a circular table. The table is supported by many legs, each bearing some portion of its weight. The table is old and somewhat lopsided, so each leg does not necessarily support the same amount of weight as every other. On top of the table are a number of bricks, each of varying mass. The larger the combined mass of the bricks, the more likely it is that the legs will be unable to support total weight, and table the will come crashing to the floor. Conversely, the larger the combined weight the legs are able to bear, the higher will be the total mass of bricks the table will be able to support.

In this analogy, the table represents our (potential) justified belief in the truth of Christianity. Each brick represents a piece of evidence/argument/observation/fact/etc (henceforth simply ‘evidence’) which makes it more difficult to retain justified belief in Christianity; that is, the bricks are evidences against the truth of Christianity. Each leg represents a piece of evidence which supports our justified belief in Christianity. No single leg alone need bear all the weight of ‘justifying’ Christianity, but the combined weight they bear must be at least equal to the total weight of the bricks. (I don’t think it much matters if the tabletop itself is thought of as having weight or not.) The number of bricks is not important, because a single very heavy brick could be enough to bring down the table. Likewise the number of legs is not important, for a single sufficiently sturdy leg could be enough to support a very large weight.

Our first task is to examine what are the key legs supporting the table, and what are the key bricks pushing down on it. The next step is then to estimate the total weight of the bricks, and compare it to the total weight bearing capacity of the legs. The purpose in approaching the problem this way is that everyone seems to have their own intuitive sense of whether the table stands or falls, but without some way of more carefully identifying which legs support how much weight, it is very difficult (perhaps impossible) to adjudicate disagreements about the table as a whole. My aim here is to try to break the question down into smaller parts, and see whether those parts represent bricks or legs. I will not, in this piece, attempt the second step of weighing up the weight supported to the total weight of bricks.

The Technical Version: Taking Partial Derivatives

The following is a more formal account of the approach outlined in the analogy above. If you find it confusing, skip this section.

Consider a differentiable function f(e), which maps a vector of evidences e onto a real number in the interval (0,1), which number represents our degree of justification or support for 4 given 1-3. The partial derivative of f with respect to each ei represents the bearing that evidence i has on our degree of justified belief in 4. If the partial derivative is zero, the evidence is irrelevant and can be ignored. If the partial derivative is positive, the piece of evidence provides support for 4, while if it is negative it provides evidence against it.

The taking of partial derivatives is important, because in practise we do not know the functional form of f, but we may be able to determine the sign of each partial derivative, and hence the relevance of each piece of evidence considered individually. We may then attempt to heuristically estimate the plausible magnitudes of these partial derivatives, and hence arrive at a judgement concerning the overall strength of the arguments for compared to the arguments against, even in the absence of exact knowledge of the form of f.

In the following section, when I speak of a piece of evidence e1 being ‘more consistent’ with state of affairs A than state ~A, I mean something like ‘P(A|e1) > P(~A|e1)’, where P is understood to be the marginal distribution over all other evidences ei (that is, we are considering the partial effect of e1 alone on our belief).

The Evidences

The reader will note that there are eight ‘against’ arguments and only six ‘for’. No doubt that this reflects, in part, my own personal bias and limited perspective. It is important to note, however, that as I stated previously, the number of arguments is irrelevant, not least of all because whether a given ‘argument’ is split up into sub-parts or combined into a single whole is arbitrary. The important question is the relative combined ‘weight’ of the ‘bricks’ (arguments against) compared to the combined ‘weight-bearing capacity’ of the ‘legs’ (arguments for). I make no claims to answer that question in this piece – here I attempt only to outline the key arguments, and indicate which ‘direction’ I believe they point in, that is in favour of 4 or in favour of 4′.

Against (‘Bricks’)

For (‘Legs’)

SufferingGiven 1-3, then ceteris paribus the amount and degree of suffering in the world is more consistent with 4′ than 4, given that 4 entails that God is all good and loving.
Resurrection AppearancesGiven 1-3, then ceteris paribus the reports of Jesus appearing to many groups of people following his death is evidence in favour of 4.
Conversion of PaulGiven 1-3, then ceteris paribus the sudden and unexpected conversion of Paul is evidence in favour of 4.
The Empty TombGiven 1-3, then ceteris paribus the early accounts of Jesus’ tomb being found empty by women is evidence in favour of 4 over 4′.
Cognitive Biases and Social InfluencesGiven 1-3, then ceteris paribus the sorts of cognitive biases, memory failings, and social influences that I document in my HBS model are evidence against 4 and in favour of 4′, since by such processes beliefs in miracles and divine revelation can (at least to some degree) develop in the absence of any actual divine intervention.
Immoral CommandmentsGiven 1-3, then ceteris paribus the numerous immoral commandments in the bible (very harsh penalties in Law of Moses, genocidal orders, treatment of women, condoning slavery, etc) are evidence in favour of 4′ over 4, given we would expect God to reveal a fair, just moral law, but would not necessarily expect this given 4′.
Cultural BoundednessGiven 1-3, then ceteris paribus the fact that Judaism and later Christianity were for most of history only accessible and known to a small fraction of the world’s population is evidence against 4.
Size and Staying PowerGiven 1-3, then ceteris paribus the fact that Christianity is the world’s largest religion, with a significant presence across large parts of the world today, and having survived many centuries of change and disruption, is evidence in favour of 4 over 4′.
Doctrinal ConfusionsGiven 1-3, then ceteris paribus the significant disagreement between Christians, both historically and at present, about many important questions concerning the nature of God and of his word is more consistent with 4′ than with 4.
Subjective Religious ExperienceGiven 1-3, then ceteris paribus the very powerful feelings of peace, guidance, love, etc that many Christians feel with respect to God are evidence in favour of 4 over 4′.
Conflicting Religious ExperienceGiven 1-3, then ceteris paribus the very powerful feelings of peace, guidance, love, etc that many non-Christians feel with respect to beliefs they hold are evidence against 4.
Biblical ConfirmationsGiven 1-3, then ceteris paribus the archaeological and historical support for the accuracy of many aspects of the new and old testaments is evidence for 4 over 4′.
Biblical DisconfirmationsGiven 1-3, then ceteris paribus the conflict of certain events of the bible with archaeological and historical evidence (such as the nativity accounts and the exodus) are evidence in favour of 4′ over 4. Note: I would also include creation, the flood, the tower of babel, and numerous other events here as well, but only if they are interpreted as literal historical events. I do not think that 4 entails such beliefs, but some Christians do.
Changing DoctrinesGiven 1-3, then ceteris paribus the significant doctrinal changes introduced by Jesus and Paul over traditional Jewish teachings (e.g. superseding much of the Law of Moses, new ideas about hell, the atonement, altered interpretation of Messianic prophecies, etc) are more consistent with 4′ than with 4, given that 4 includes notions of God being unchangeable and consistent.


Irrelevant Considerations

Here I will simply list, without explanation, a number of considerations which are often raised as being potentially relevant to the question of the truth of Christianity, but which I do not believe offer particularly strong support either for 4 over 4′, or for 4′ over 4.

  • Christians doing good at present or historically
  • Christians doing evil at present or historically
  • Similarities of Christian beliefs to other religious mythology
  • The doctrine of the trinity
  • Personifications of God in the bible (e.g. speaking as if God had a physical body)
  • The religious beliefs (or absence thereof) of Hitler, Stalin, or Darwin
  • The existence or findings of science (aside from certain findings of psychology and archaeology, as outlined above)
  • The coherence or compellingness of Christian doctrinal teachings

Some Personal Reflections

I will conclude with a few brief thoughts about where I personally stand currently on weighing up the evidences. Very loosely, I tend to think that the biblical confirmations and disconfirmations roughly ‘cancel out’ (i.e. the weight added by the brick of disconfirmations is roughly the same as that supported by the confirmations). I think likewise that subjective experience is roughly cancelled out by conflicting experiences, and that cultural boundedness is roughly cancelled out by size and staying power, though in these cases I might lean towards saying that the bricks are somewhat heavier than the corresponding legs support. I think that the cognitive biases brick noticeably outweighs the resurrection appearances, empty tomb, and conversion of Paul all combined. I tend to think that suffering, immoral commandments, and doctrinal changes are problematic bricks without any sufficiently compensating load-bearing legs, though I am not especially confident about this. I also suspect that (given my bias) this list is more likely to omit some important ‘legs’ than it is likely to omit some important ‘bricks’.

Overall, I am left with a conviction that even given 1-3, Christianity is noticeably, but not overwhelmingly, more likely to be false than true. Maybe I’d put my subjective degree of belief (again, conditional on 1-3) at around 0.2, which large margins of error. Though strictly speaking outside the scope of this piece, I would accord a similar, though perhaps slightly higher, degree of belief in 1-3 themselves, for which reason I call myself an atheist. The truth of the matter is, of course, not in any way affected by my degree of belief. Nevertheless, I want to hold true beliefs and avoid falsehoods, and this article represents a summary of my recent manner of thinking about how to best achieve this goal. I hope it will be of use to others and simulate further discussion and profitable exploration of these important ideas.


4 thoughts on “Weighing up the Arguments For and Against Christianity

  1. Hello again. Interesting article.

    I would like to share a particular point partially related to personal experience but also as a comment.

    The whole question of is it true or is it false is definitely of interest to many people.

    Let us, for arguments sake say that the evidence for particular events didn’t stack up.

    Let us be really bold and say that it was possible to fully prove the falsehood of all the events and metaphysical nature of the Christian message. (Just for argument sake)

    However, if some part of the, shall we say mythology, is capable of transforming human lives for the better – is this a good or bad thing overall?

    So maybe to put it another way.

    If the result in a person’s life and the lives of the people around that person was better because they ordered their life around the “mythology” (for want of a better term) than if they did not…..then does that imply that the actual true/false question is of lesser value?

    Yes of course there are examples of the reverse as well…

    What if human psychology and biology( thanks to millions of years of evolution) is such that the Christian message – regardless of its truth or falsehood – has the ability in some cases to transform lives for the better?


  2. Thanks James. This is very well articulated.
    Is the “table leg” of Jesus’ birth, acts, persecution and death fulfilling prophecy written in the Old Testament not included as it is completely negated by concerns about “altered interpretations of Messianic prophecy” in your consideration? I’d like spend more time hearing about the idea of altered interpretations of Messianic prophecy but I should think that a change in interpretation of a prophecy is unlikely to indicate a changeable character of God but rather indicates something about those interpreting.
    Also, I feel that many of Jesus’ teachings and claimed acts relate closely to and fulfill God’s plans articulated in the Old Testament, namely to bless all nations through a descendant of Abraham (which Jesus does by opening up the ability to be know God to the whole world through his atonement and by sending out his disciples to tell Jews and Gentiles) and to redeem Israel. Perhaps this goes some way to take the weight of apparent changing doctrines.


  3. I’ve had a few people mention OT prophecies allegedly fulfilled by Jesus of late. I shall have to investigate the issue further and write more about it in due course. My initial reaction is that basically all religions claim to have fulfilled prophecies, and I’m always concerned as to why Christian interpretation of the OT should be privileged over Jewish interpretations, which do not seem to agree that Christ fulfilled the Messianic prophecies well at all.


  4. Pingback: The Question of Christianity: A Personal Manifesto | The Godless Theist

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