Bertrand Russell made many objections to Christ and Christianity in his paper Why I am not a Christian.

When considering arguments for the existence of God, Russell states, “Perhaps the simplest and easiest to understand is the argument of the First Cause. It is maintained that everything we see in this world has a cause, and as you go back in the chain of causes further and further you must come to a First Cause, and to that First Cause you give the name of God. …If everything must have a cause, then God must have a cause…There is no reason why the world could not have come into being without a cause; nor, on the other hand, is there any reason why it should not have always existed.”

Russell fails to see that if the world could have come to be without a cause so could God. And if the world could always have existed then why not God? His arguments do not work unless the concept of God is incoherent. It is incoherent and that is the problem with it.

Imagine the first cause was just an impersonal and spiritual intelligence. That would be simpler than the Christian God who not only is intelligent but is conscious and can relate to people. If you want an simple first cause, the cause cannot be God.

Christians say, "Russell believed in the brute fact of the universe. He didn’t see that it is more likely for God to be such a fact than the creation. God is simple and he is spirit. Spirit is that which exists but which is not physical and has no parts. The creation however is complicated and physical and needs to be put together and organised. He failed to see that when we say everything has a cause we mean the creation. God was not made by anything. He has no cause. He just is. God is a brute fact. Only God can be a brute fact for he is the reason for his own existence."

This assumes that a spirit is so simple that it needs nothing to put it together. But that may be false - sometimes simple things have to come out of complex. It assumes that it is good and perfect to be God. But is it?

You would need to be able to prove spirit really exists. And you would need to prove that being spirit is good. In fact, Christians say we hope to rise again implying that surviving death as a spirit is undesirable and inadequate. It is only good because the alternative is non-existence. That would be a negative goodness. It is not a positive goodness. So it might not be good to be a spirit. It could be a case of being wanting to do things and being unable to without having a body. Or it could be a case where you have no brain or nerves and no feelings and just float around aimlessly. A spirit God as a spirit God, cannot suffer for others. God is said to have become man in Jesus Christ. But that is different. He had to take on an additional nature in order to do it.

Russell is said to misused Occam’s Razor. Occam’s Razor means one must always accept the simplest and most suitable explanation of the available evidence. Suppose the universe could be a brute fact. Suppose God could be a brute fact. Occam’s Razor says we should take it for granted that God as the simplest adequate explanation is the brute fact. Russell could have avoided being accused of abusing the Razor by exploring the alleged simplicity of God more in depth.

“There is a very common argument from Natural Law. That was a favourite argument all through the eighteenth century, especially under the influence of Sir Isaac Newton and his cosmogony. People observed the planets going around the sun according to the law of gravitation, and they thought that God had given a behest to these planets to move in that particular fashion, and that was why they did so… We now find that a great many things we thought were Natural Laws are really human conventions. You know that even in the remotest depth of stellar space there are still three feet to a yard. That is, no doubt, a very remarkable fact, but you would hardly call it a law of nature. And a great many things that have been regarded as laws of nature are of that kind.”

Russell attempts to refute the idea that the universe works according to laws - eg, its law that if you get too close to the sun you will burn up - because he is afraid that the suggestion that it does imply that there must be a God to make these laws. He suggests that what we see as natural laws are simply the regularities we observe. They are not really laws. In this view, the sun is hot not because laws actually decree that it will be but by chance.

This is an example of circular reasoning, “The universe does not really work through laws so there is no God. Because there is no God we know it does not work by laws.” He is assuming as true what he says he needs to prove. Assuming is not proving.

Russell fears the notion that there can be no law without a law maker. But if there is no God, if there is nothing at all, it is the law that there will be no suffering. Laws exist whether there is a lawmaker or not.

Russell contemplates the Argument for God’s existence From Design:

“The next step in the process brings us to the argument from design. ..When you come to look into this argument from design, it is a most astonishing thing that people can believe that this world, with all the things that are in it, with all its defects, should be the best that omnipotence and omniscience have been able to produce in millions of years. I really cannot believe it. Do you think that, if you were granted omnipotence and omniscience and millions of years in which to perfect your world, you could produce nothing better than the Ku Klux Klan, the Fascisti, and Mr. Winston Churchill?”

Christians reply, "Russell assumes that God must make only perfect things. If for him if things are imperfect or seem to be imperfectly designed then they disprove God. He does not consider the possibility that creation was designed well but we ruined it. We ruined the design at the Fall. The ruin does not refute design but rather supports it."

If design is ruined by evil, that evil surely might attack our minds first and foremost. So how can we judge then if creation is designed? Is not blaming the fall for the lack of design an attempt to dismiss any evidence that there is no design?

Another Christian answer to Russell’s problem is that God does make things perfectly. It is because we refused to be perfect that creation is imperfect. Also, an artist might design some “flaw” into his painting. That does not mean his painting is imperfect. It is as perfect in the way it is meant to be.

If we were in a hellish universe, Christians would still be saying that. It is rubbish spouted by people who have no real understanding of the horrors of suffering.

Christians say, "Russell thinks that the things that don’t seem designed prove there is no designer. If you go into a tailor’s premises and see there are a few coats completed amid a pile of material lying everywhere you will not take the latter as evidence that there is no tailor. You will take the coats as evidence that there is."

But if the rags were found along the road you would not say there was a tailor there. You only take the rags as evidence for a tailor when you know you are in a tailors shop.

Russell argued:

God only makes things that look perfectly designed.

There are imperfections in the universe.

Therefore there is no God.

He takes the first premise as proven though it is only an assumption. It is not necessarily correct. But it is not necessarily wrong either.

He says, “Really I am not much impressed with the people who say: "Look at me: I am such a splendid product that there must have been design in the universe." I am not very much impressed by the splendour of those people."

He insinuates that believers in divine design are arrogant and haughty. That is an ad hominem argument. If all believers have that pompous attitude it does not disprove divine design. He is trying to provoke ill feeling against believers to prejudice the reader against divine design.
The argument would show that believing in divine design is not nice but not that it is incorrect.

After stating that life will disappear from the universe one day and there is no eternal life he writes, “I am told that that sort of view is depressing, and people will sometimes tell you that if they believed that they would not be able to go on living. Do not believe it; it is all nonsense. “

It seems true that some people need the teaching of eternal life. In fact, they make themselves need it. If they were properly adjusted they would love life for being life and settle for that. In reality, what they need is not the belief but to grow out of it.

He argues against the moral argument for God which states that “there would be no right and wrong unless God existed. I am not for the moment concerned with whether there is a difference between right and wrong, or whether there is not: that is another question. The point I am concerned with is that, if you are quite sure there is a difference between right and wrong, then you are then in this situation: is that difference due to God's fiat or is it not? If it is due to God's fiat, then for God himself there is no difference between right and wrong, and it is no longer a significant statement to say that God is good. If you are going to say, as theologians do, that God is good, you must then say that right and wrong have some meaning which is independent of God's fiat, because God's fiats are good and not bad independently of the mere fact that he made them. If you are going to say that, you will then have to say that it is not only through God that right and wrong came into being, but that they are in their essence logically anterior to God.”

Russell’s argument is obviously and undeniably correct. No honest person will dispute it. No decent person will say that the problem with killing babies for fun is not that it needlessly hurts the babies but that it is forbidden by God. To be unable to admit it is bad just because it is cruelty is to admit that you don't really know what evil or good are.

Christians dispute Russell's argument. They say its flaw is that it is too simplistic.

Some say, "If there is no God who is working to bring a greater good out of all the evil that happens, then for all you know, murdering a baby could change the course of history for the better and letting the baby live might not. Everything we do has a “butterfly effect” or domino effect. Every event however small ultimately changes the course history will take. So you have no way of proving that it is really right or wrong. To believe in the possibility of knowing the objective moral values you need to believe in a God whose authority forbids us to murder babies." An atheist would not kill the baby for he has no reason to think it can better the future. The believer in a God who turns evil into good could not agree with the atheist. The argument they give is no response to Russell. Russell is not on about what is moral or immoral but about the justification for believing that morality is real.

Is wrong really wrong or is it wrong just because God says so? If we say the former it implies that right and wrong are independent of God and God must obey those standards. The Christian "solution" is that God’s character is good and he only commands good because he is good. There is no standard of good and evil independent of God. Thus good and evil have objective existence. In reality, the solution says that both options are out and then it combines them and rewords them to make it seem there is a third option.  Why is God's character good?  So the new answer takes us back to where we started!

Christians try to put God outside the reach of science by saying he is not an object in the universe and science is about objects in the universe. But what about science and his Bible? Science disproves the Bible.

“ The whole conception of a God is a conception derived from the ancient oriental despotisms. It is a conception quite unworthy of free men. “

This is stating that we are superstitiously doing away with our freedom by believing in God because it is derived from ancient despotism. Russell forgets that the Christian God is a God of liberty and freedom. He wishes us free us from slavery to sin. He makes an ad homimen attack on belief in God. Even if belief in God did take away our freedom and happiness it still would not follow that it is false.

And another logical error is that if belief in God came from ancient despotism, it does not mean that it is a bad doctrine now. Ideas can be started off by bad people and evolve into good things. Again Russell has made an ad hominem attack not on God but on belief in God. However, if the despotism is commanded by God in the scriptures and they are considered inerrant, belief in this God and in his scriptures could prove dangerous.

Conclusion: Russell some logical errors in Why I am not a Christian. But overall the book does a reasonable job of refuting Christianity.