Science has transformed the world around us. After hundreds of thousands of years existing as a species, in only a few centuries, the world has been changed forever. The scientific method has so far been the most reliable way human beings have ever discovered for gaining knowledge and resolving disputes about facts (save perhaps mathematics).
Given that it is so reliable, can we say that all questions can be answered scientifically, that is, by the application of the scientific method to evidence?
If so, then we are certain to gain all knowledge in the universe that can be had in a reliable way.
If not, then a further question is: can we know anything that cannot be obtained through the scientific method?
Before we get into these questions, it’s best to define terms. Many people implicitly assume these days that to know something is to obtain it from science. That is not what I mean here because then the logic would be a tautology (a self-implying statement). That is: to know = to obtain with the scientific method. If that were the case, we might as well stop now.
There is a whole field of philosophy about what it means to know something called epistemology. I am not going to get into all the details here. Instead, when I say you can know something I mean precisely this: that you are reasonably justified in believing it.
By reasonably justified, I mean justified by logic, not feelings, intuitions, dreams, authority, or personal experiences. Logic, in a Socratic sense, means that based on some set of premises that are reasonable, you proceed logically to a conclusion. As long as your premises are true, your terms well defined, and your logic sound, you can be reasonably justified in the conclusion.
Where do premises come from? They come from data but not necessarily scientific data. Instead, they come from any and all information we perceive about the world: these can be mathematical, moral (like “it is good to be good
), or inferences about how the universe works such as causality. What these premises have in common is that they tend to be shared by reasonable people. That is, few are willing to accept their negation (though some may and develop whole philosophies based on such premises). It makes little sense to make a logical deduction based on premises that no one accepts.
Now, the question isn’t, “is it possible to know anything without using science?” I just said that to know something didn’t necessarily mean to obtain through science. Instead, the question is whether everything knowable can be obtained through science, but that does not precluded obtaining that same knowledge, in a less reliable way, through other means.
Well, I can put that question to rest right away because the single foundational assumption of science is that science exists. In other words, science assumes that the world works in a reliable, repeatable way, through sets of definite rules that justify the evidence of experiment. Without that assumption, the scientific method would be wrong. We, as reasonable people, accept the premise that science does exist, and we can call that knowledge because reasonable people are justified in believing it, yet it is not obtained though science.
Another axiom is Ockham’s razor. Willem of Ockham was a 13th century English philosopher, and he stated that one must not multiply hypotheses needlessly. In other words, accept only the simplest hypothesis that explains all the evidence. Ockham’s razor is an axiom because no evidence supports it. It is rather self-evident and reasonable people are, again, justified in believing it. Nevertheless, it is critical to the development of science.
Another, rather large area includes all of mathematics which, we can say, is far more reliable than anything the scientific method has given us. We know that 2+2=4 always and forever. We can’t say that about any scientific theory.
Logic itself upon which mathematics is based is assumed to exist. There is nothing that tells us that rationality is real. It could all be a trick of evolution that our monkey brains want us to believe that logic is real. Indeed, logic is intrinsically tied to some kind of language: verbal, as it making statements and defining terms in ordinary human languages, notational, using a formal notation like mathematical symbology, or visual, as in using pictures to make logical arguments. Language is one of the defining attributes of human beings that does not exist in non-living things. Therefore, could we say that logic, along with language, is simply an evolutionary adaptation?
Yet, how many reasonable human beings accept that? Perhaps a few materialist philosophers would but certainly not the man or woman on the street nor mathematicians nor scientists.
What about moral truths? Basic ideas like it is good to be good. Well, Nietzsche disagreed and a few others followed him, but most reasonable people would agree with that premise. I can think of no scientific way to settle that question. Can you prove Nietzsche wrong? Just because the negation of that axiom leads to horrors doesn’t prove anything, only that we believe the initial premise is true by calling the results horrors and indicating those horrors are bad things.
Science has no control over abstractions, but what about ideas about the universe itself? Let’s look at cause and effect. It has long been an axiom that cause precedes effect. Indeed, this is one of the premises in the original form of the Prime Mover justification for the existence of God. It turns out that experiments in quantum mechanics have shown that cause and effect can be switched. Yet, is this an example of science disproving a philosophical axiom, one that is supposedly science-proof or is it really a matter of ill-defined terms?
In these quantum experiments, it is possible to set up an experiment where it is ambiguous as to whether effect followed cause or vice versa. It is not possible, however, to create any kind of paradox this way, like a time traveler paradox where you definitely have a violation of causality. In terms of measurable causes and effects as the transmission of information from cause to effect, causality is still preserved even in these experiments. So far we have never demonstrated a true causal violation as you might see with time travel. For now, it seems that our definition of cause and effect as it relates to quantum mechanics vs. classical might be too broad, and we should confine cause and effect to the transmission of measurable information.
While the scientific method supposes the axiom of causality (and certainly causality is a falsifiable scientific hypothesis, though it seems unlikely to be false) it can never prove it to be true. Indeed, science can’t prove anything to be true in the same way that logic can in mathematics. Scientific theories, far from being true or false, are simply better or worse.
The philosopher Karl Popper argued this in his theory of falsifiability. Essentially, science works like this: scientists observe some unexplained phenomena, they propose many reasonable sounding hypotheses, they test each one and attempt to falsify it until only one hypothesis remains, that hypothesis is then considered to be scientific fact. One can, however, come up with a new hypothesis that explains more and falsify the old hypothesis. This is what happened in 1919 when Einstein’s theory of general relativity was shown to bend light by the correct amount around the Sun, falsifying Netwon’s theory of gravity (which couldn’t explain light bending).
Popper’s work suggests that science does not establish truths. Rather it reliably sorts best theories from the worse theories, similar to how Ockham’s razor sorts hypotheses. Thus, relativity is not a true theory but our best theory, which is why, even now, we are trying to prove it false because by falsifying one of our best theories we invite the development of a better hypothesis that explains the evidence.
Popper’s work can also be applied to areas that are not necessarily scientific such as moral philosophy, but in that case the standard for evidence is not experiment but people’s intrinsic moral beliefs. Understanding what the reasonable person believes about right and wrong can help us to “falsify” our moral premises. This is why moral philosophers conduct studies where they try to determine what moral choices people naturally make by presenting them with moral dilemmas. A classic example is the “trolley problem”, where given a runaway trolley about to hit five people, would you pull a lever to cause it to hit just one person?
Most people say they would pull the lever, but, if you modify the problem in various ways, it becomes more ambiguous. For example, if you had to push somebody physically in front of the trolley to save the five people, most people would not do it. If the one person was a loved one, again, most people aren’t utilitarian enough.
Consider the moral issue of saving lives through organ donation: is it moral to kill somebody, harvest their organs, and use them to save five people? Most people would say no. What if that person died but did not consent to organ donation? Perhaps a little more ambiguity? Details matter in moral questions and hence in order to be intelligible, premises have to be well-defined as to the details of the moral question. Philosophies like pure utilitarian morality, which posits making the greatest number of people happy, fail these basic tests of reasonable premises.
This does say that the scientific method can make our conclusions about things that seem unscientific more reliable such as what is right and wrong. By conducting studies of what people believe, we can enhance our understanding of what a reasonably justified premise is and help us to refine terms. Nevertheless, it cannot provide the kind of reliability that we have with studies of cause and effect in physics or chemistry. All it can do it collect more data so we better know what a reasonable person believes. It cannot make those beliefs more scientific.
When it comes to other questions like is there a God? We can say a lot by making reasonable premises and drawing logical conclusions from them. Most of the arguments against the existence of God were invented by Christian philosophers such as St. Augustine and St. Thomas Aquinas. They wanted to know how tough their beliefs were in a logical sense. A classic set of four statements about God is as follows:
God exists.
God is all good.
God is all powerful.
Evil exists.
A classical philosophical conundrum is that not all of these statements can be true. At least one of them must be false. The logical reasoning is that an all good, all powerful God would not allow evil.
Atheists deny the first one: God exists.
Few would be willing to deny the last one: evil exists. Can you prove scientifically that evil exists? No, evil is about human actions and science makes no moral judgements about those actions. You have to ask people.
Buddhists would deny that #1 has an answer. Hindus might deny #2. Other polytheists might deny #2 and #3.
Members of Abrahamic religions, Christianity, Judaism, and Islam, would not deny any of them outright. Instead, they would either argue that the terms are ill-defined or that the conclusion that an all good, all powerful God would prevent evil is erroneous. The Book of Job in the Bible makes this argument. Job complains to God about his ill-treatment and God says, “don’t question me. I know what I’m doing.” Perhaps the evils of the world are good for us, some argue, a necessary rite of passage towards the afterlife and salvation. Just growing pains during a short life followed by an eternity of bliss. Thus, by not preventing evil, perhaps even by permitting it, God is actually doing good.
Others argue that human beings invented evil, not God. God only made good things but also gave them free will so that they might do good or evil themselves. This is the argument the Book of Genesis makes, but hardly explains why bad things happen to good people.
Some Christians would argue that, through Christ, God is bringing evil into subjection under Him and that to defeat evil is a better thing than evil not existing. Thus, evil is allowed because it must be mastered by God and humans alike, and this is more good than not allowing evil in the first place or God waving a magic wand and removing it from the world.
We can go on and on with dozens more arguments, but science can contribute little to this discussion. It cannot disprove God unless you tie your belief in God to the denial or acceptance of a scientific theory, which is stupid. Likewise, the basis of science, that it exists, is no more supported by science than God. Nor can science resolve the problem of evil. Science can show a wide variety of moral standards among different human populations. There are places and tribes where every single one of the ten commandments is regularly violated. It is hard, however, to argue that there is no moral standard. Most reasonable human beings would not want to accept the consequences of that belief because it could be used to justify all kinds of horrific behavior. Once you accept that there is no moral standard, you are restrained only by how hard the rest of society tries to stop you. Might makes right.
In conclusion, it turns out that while science cannot grant us all knowledge, we can obtain knowledge about the answers to some important questions like: What is right and wrong? How do we know things? Is there a God? through logic and questioning, based on reasonable premises. While some may argue that we are just playing with subjective beliefs, few would accept that all human knowledge is subjective. Some might argue that the idea of objective knowledge is just a convenient fiction. We believe it because the practical consequences of not believing it are too awful to contemplate. That is certainly a thought worth entertaining. Unfortunately, that would imply that the notion that knowledge is subjective is itself subjective knowledge, so it is, if not self-defeating, amusingly impossible to justify.
In this article, I did not want to present a formal analysis but more of an exploration of the topic, so I have played fast and loose with some terms and arguments. There are a mountain of alternative philosophies and objections that can be brought to bear on any of these points. All these things are good. It is always good to have more objections and more arguments than fewer because that just helps refine our data better. In this sense, philosophy has the same overarching desire as science, even if it deals with data that is less reliably collected.