Certainty is not possible in science

Question

So I have formulated a set of arguments to argue certainty is not possible in science. Did I make an illogical argument here or like is there anything amiss in my argument?

Opinion: Science can reach an absolute truth, but we will never be certain of it.

Argument: We are limited by our consciousness. Every experimental design we construct is limited by our thinking. Every observation we make is made through the human lens. We don’t have the ability to detect unseen realities. Therefore, we cannot test if they are there or not. This is why we can’t be sure our model of reality is absolute truth.

Argument: We are not fortune-tellers Since science is prohibitive (rules out possibilities), some ideas don’t fit our reality, others do. We create theories and test them. But we don't have the ability to tell if the next experiment will prove the theory wrong. A theory that withstands all the tests so far could easily fail at the next so we can’t be certain that it holds. So certainty that our theory is absolute truth is not possible. This pattern of new models replacing old ones is a paradigm shift and what is common today was radical before.

Argument: We make assumptions Every theory we construct is based on a set of assumptions. For example, the theory of relativity matches really well with what we measure but it assumes the speed of light is constant which we do not know is true. Since we make assumptions which, for the above paragraph reasons, we can never be certain, then the theory built upon it has no 100% certainty of being true either.

Conclusion: So maybe a better way of defining science is not a process to find the absolute truth but rather a continuous process of modeling what we see to the best accuracy possible.

Answer 1

Science is not a goal, it is a methodology. Within this paradigm is the certain knowledge that the results of scientific endeavor will always be tentative, subject to further refinement as technology advances and as new models of physical phenomena are proposed.

So, Aristotle thought that rocks fall because their natural state is on the ground. Newton proposed that rocks (and apples) fall because of an inverse-square law in three spatial dimensions that is scaled by the product of the gravitating masses and a constant of proportionality to make the units come out right. Einstein then showed that Newton's gravity was caused by spacetime curvature and would yield incorrect results in the extreme case of enormous masses of small size (which were unknown in Newton's time). And it is already well-known that Einstein's model of gravity will fail to furnish correct results when we try to apply it to the singularity inside a black hole.

In the push to advance scientific understanding, we are no longer limited by our human senses: we have telescopes and microscopes that allow us to make images of things our eyes cannot see, and thereby remotely detect the falling of trees in forests we do not inhabit.

For example, the SLAC linear accelerator allowed us to probe the insides of a proton and determine its internal structure, giving us the ability to detect the "unseen realities" there in the same way that the Hubble and Webb telescopes let us probe the unseen realities that lie within galaxies that are 10 billion light-years away from us.

Regarding fortune-telling, I don't know what your point here is exactly but I will say that all models have limited ranges of applicability outside of which they cannot provide correct predictions- but that this characteristic does not disprove the model within its range of applicability.

Regarding assumptions, note that it is a very common exercise to discard specific assumptions when building models and then seeing what if anything the resulting model will correctly predict. If the predictions remain true, then the initial assumption was in fact unnecessary. If the predictions become false, then the model requires the discarded assumption- which in and of itself provides further clues to understanding the way the universe works.

Answer 2

Opinion: Science can reach an absolute truth, but we will never be certain of it.

No it can't for the simple fact that for that we'd need to measure with absolute certainty and that is, so far, considered to be a physical impossibility. For example Heisenberg's Uncertainty relation argues that location and momentum can't be measured at the same time with "high" accuracy, so together they can't be more exact than 34 decimal places. So you won't really see the effect of that in real life but if you wanted to get to the bottom of physics and describe small things with the best precision that you can get, you get into the trouble that this isn't even physically possible.

And that's just one problem, there's also quantum mechanics where we can't actually measure the thing itself but just the probability and the combination of the previous two with chaos theory, that is the problem that little variations in the starting conditions of certain experiments can lead to huge deviations of the results over time means that "truth" is kinda out of reach.

So what ever "truth" is produced by science will always have a margin of error. Or in other words won't be a truth to begin with.

Argument: We are limited by our consciousness. Every experimental design we construct is limited by our thinking. Every observation we make is made through the human lens. We don’t have the ability to detect unseen realities. Therefore, we cannot test if they are there or not. This is why we can’t be sure our model of reality is absolute truth. _whatisscience_Scientific method

Yes but no. As long as we can perceive that effect in any possible way we might construct a device that can measure or amplify it so that we can detect it and at that point we can describe a lot of things with reasonable certainty that no human has ever see with their own eyes (directly).

Argument: We are not fortune-tellers Since science is prohibitive (rules out possibilities), some ideas don’t fit our reality, others do. We create theories and test them. But we don't have the ability to tell if the next experiment will prove the theory wrong. A theory that withstands all the tests so far could easily fail at the next so we can’t be certain that it holds.

Ironically that is the process of science. We try to tell the future using only our models and if they are good, then the future actually comes out as predicted, if not we scrap or update our models. If it were just for that we could actually find truth, but as said we build models on flawed data and so we can't get around the margin of error. But as Popper defined it. Science is always wrong. Being wrong and having the ability to be proven wrong is not a weakness but a strength. A theory that explains everything perfectly and can predict the future wouldn't need science.

Argument: We make assumptions Every theory we construct is based on a set of unquestioned assumptions. For example, the theory of relativity matches really well with what we measure but it assumes the speed of light is constant which we do not know is true. _whatisscience_science is a human construct

Yes and no. I mean there are fundamental assumptions about the world, but if reality showed them to be wrong, they would still become subject of scrutiny if that's what you're trying to say.

Conclusion: So maybe a better way of defining science is not a process to find the absolute truth but rather a continuous process of modeling what we see to the best accuracy possible.

Isn't that already the definition of science?

Answer 3

No method we know of can determine "absolute"/objective truth, because all knowledge builds on our subjective and limited perception of reality.

This is already accepted as true by many/most people, or at least most philosophers, skeptics and scientists. So no argument to support this is necessary.

Science is the best we've got though, and it's essentially just the formalised process for how humans (and other animals) naturally gain knowledge.

Every theory we construct is based on a set of unquestioned assumptions.

Kind of, but not really, no.

All knowledge is based on some assumptions, but science and the scientific community is pretty good at breaking down, questioning and "proving" or "disproving" (i.e. providing evidence for or against) those assumptions.

Whether assumptions are questioned is not a function of science itself, but rather of the humans applying said science. If you think specific theories are based on specific assumptions that should be questioned, but aren't, and you can present a good reason why it should be questioned, or why it might be false, scientists would probably like to know that.

Although science isn't typically so much about building on "unquestioned assumptions", as much as it's about trying to come up with the simplest explanation for observed reality. Sometimes we observe more things so that explanation stops being the simplest one (or breaks apart altogether). In that case, we come up with another explanation. Or if we come up with an explanation that's simpler or better explains reality, we opt for that instead. This is exactly what makes science as useful and powerful as it is: it's constantly improving and refining itself as our knowledge of reality expands, and it typically doesn't add unnecessary or unjustified assumptions when our observations can be explained without those assumptions.

... but it assumes the speed of light is constant

This sounds like a good example of an assumption we've questioned (directly or indirectly). We've tested the speed of light quite extensively.

Although I suppose it depends on in which way you think we're not questioning whether it's constant (and why and how this would impact the theory of relativity).

[defining science as] a continuous process of modeling what we see observe to the best accuracy possible

This is a reasonable (if incomplete) representation of how science is already defined, based on how scientists and many laypeople already view it. You'll probably also need to include the systematic nature of the process, and the usage of the scientific method, in the definition though.

Answer 4

Science can't reach infallible truth, but scientists can create knowledge we can act on, as explained by the philosopher Karl Popper among others.

Argument: We are limited by our consciousness. Every experimental design we construct is limited by our thinking. Every observation we make is made through the human lens. We don’t have the ability to detect unseen realities. Therefore, we cannot test if they are there or not. This is why we can’t be sure our model of reality is absolute truth.

This is wrong. All of our observations are conducted using experimental apparatus that is constructed in such a way that they can distinguish between two or more theories about how the world works. If theory A is true the result will be X; if theory B is true the result will be Y. So if we get X A might be true and if we get Y then B might be true. If we get some other outcome Z then they might both be wrong. When we get a result that is incompatible with some theory, that is a problem for the theory and has to be addressed either by discarding the theory or by pointing out a problem with the experiment. So we can eliminate theories through experiment.

Argument: We are not fortune-tellers Since science is prohibitive (rules out possibilities), some ideas don’t fit our reality, others do. We create theories and test them. But we don't have the ability to tell if the next experiment will prove the theory wrong. A theory that withstands all the tests so far could easily fail at the next so we can’t be certain that it holds. So certainty that our theory is absolute truth is not possible. This pattern of new models replacing old ones is a paradigm shift and what is common today was radical before.

This is true.

Argument: We make assumptions Every theory we construct is based on a set of assumptions. For example, the theory of relativity matches really well with what we measure but it assumes the speed of light is constant which we do not know is true. Since we make assumptions which, for the above paragraph reasons, we can never be certain, then the theory built upon it has no 100% certainty of being true either.

Your theory is either right or wrong. So there's no point in trying to attach probabilities to theories. Rather, you should judge a theory as either true or false - you should say yes or no. Your judgement might be right or wrong and you should look for criticisms of your ideas, but that's not the same as attaching probabilities to theories.

Answer 5

What you conclude is generally agreed upon, give or take a few word choices. That being said, I find the phrasing of the conclusion to be rather thorny. It is pounced upon by many detractors of science, making debates more difficult than they need to be. Instead, I like to start with the opinion that science, and more specifically the scientific method, is a part of Empiricism, a school of thought about truth that argues that truth is derived from sensory experience. To my knowledge, this is a universally agreed upon opinion, making it a useful first step. Your first two arguments, the "limited by our consciousness" argument and the "we are not fortune-tellers" argument are fundamentally tied to Empiricism, not just the scientific method. And it is generally accepted that empirical methods "make assumptions," although that one might have to be debated more carefully. So we can widen the net from making these statements about science to making these statements about empirical thinking in general.

I find this to be value added because the debate about knowledge and truth has been going on for a long time, and those particular word choices have a great corpus of content to work with. For example, Empiricism is considered to be a part of epistemology, the study of what can be known/is known. Another major branch of epistemology is skepticism, which is interested in the limits of human knowledge. If I may read between the lines a bit, I believe your argument is very much a skeptical one, and it is possible to look at the works of skeptics who argue these properties not only apply to science or empiricism, but human knowledge as a whole.

These are worthwhile because they point to a thorny reality that anyone who is doubting science's ability to derive truth (a well founded doubt, as described here) also need consider whether the same arguments apply to any other system or approach they might compare and contrast with the scientific method. They tie the topic into the much larger debates about knowledge that have been refined quite literally over millennia.

Answer 6

I doubt very much that most leading scientists believe that they are seeking absolute certainty. I have the impression that they are looking for models that are increasingly complete, descriptively valid, and with a high probability of making the correct predictions in new situations. That is far from absolute certainty search.

Maybe, we can agree or disagree on that, but what I see as very weak are the arguments presented:

Argument 1: We are limited by our consciousness.

There are indirect ways to corroborate things, if we are right one thing will happen if we are not right something else will happen. Moreover, technology continually opens up new ways of testing old ideas, and since science is a collective enterprise, the limitations of an individual consciousness do not restrict science as a collective enterprise.

Argument 2: We are not fortune-tellers

Indeed, we have no way of predicting whether each new experiment will confirm the predictions of the theory. But we do have the possibility of reformulating the theory to obtain models that are more likely to fit the experimental data (this is incontrovertible historical evidence).

Argument 3: We make assumptions

Yes, that is also true, but as the history of science has shown, with time there is a way to test the validity of one's assumptions, to revise them and, if necessary, to reject them.

In short, I do not believe that any of the three arguments is a serious obstacle to the purpose of science as conceived by most scientists. There are other difficulties more notorious than those mentioned, and yet it is not clear that this will prevent a continuous improvement of science, although it may be the case that some questions are permanently scientifically ungraspable.

Answer 7

The statement of the title is wrong as it is state: Math is a science, and math yields results with certainty. True, math builds only upon abstract definitions, and thus can only infer results about abstract things. Nevertheless, math is a science. The science of thinking logically, to be precise. As such, it is at the root of any other science. Physics and chemistry are nothing without math.

As I said, math is limited to the abstract world. It cannot make any conclusions about the physical world, whatsoever. If we want to get knowledge about the physical world, the methods of math alone are not enough: In a way, math starts with the rules, and works its way down to the specific. However, we do not know the rules that the physical world obeys, apriori, therefore we cannot apply the same deductive method on the physical world. We can only conduct experiments to test the specific. From those specific results, we are trying to work our way back to the rules, but this is an error prone process.

In fact, the process of inferring rules from specific experimental results is so error prone, that we can never be sure that we actually inferred a correct rule, i.e. a rule that the universe actually fully obeys. Since we can only ever run specific experiments, we may simply have forgotten about that one experiment that would prove our theory to be false. In this way, physics, and the other natural sciences may never yield results with certainty.

Nevertheless, we have run enough tests on all the established physical theories up to general relativity and quantum mechanics, that we are confident enough to trust them right up to the bounds of where we know they must break down. I.e. we know that neither theory is "correct", yet both are exceedingly precise approximations to the physical world. Enough certainty to use them confidently for every conceivable purpose, but not enough certainty to stop trying to disprove the theories. (Testing quantum mechanics and general relativity has become somewhat boring though: With the perfect track record of both of these theories, nobody is ever surprised when yet another experiment fails to report a deviation.)

Answer 8

Science can reach an absolute truth. A hypothesis may be absolutely true (leaving aside the possibility that there are no absolute truths). A given body of evidence may support that hypothesis so strongly that all scientists believe it and it is in all the textbooks. That is what we mean when we say that science has reached the conclusion that something is true.

It may be that the evidence could also be explained by some other (false) alternative hypothesis that no one has thought of. That is beside the point because scientists and textbooks aren’t thinking about that alternative hypothesis.

So in this case, science has reached an absolute truth by accident.

As for whether we can be certain that science has reached an absolute truth, the answer is yes!

People have the capacity to be certain of things. Whether the things they are certain of are true, or even justified based on evidence is only tangentially related to the psychological state of being certain.

Answer 9

'Certainty is not possible in science' Hmm, I'm not sure a mathematician would agree (I'm not a mathematician, so I could be wrong!). The part of the answer uses the phrase 'absolute truth'. I posit that there is no such thing. All 'truth' is relative (NOT subjective).

I had a lecturer who presented some well-known theories of science and observations; then proceeded to demonstrate how these were predicated on some assumptions, and changing the assumption altered the very shape of the universe.

This created a very bewildered class, who asked "How do we know that the theories and equations are correct?"

His answer was "We know they are correct because we can use them to design and build things that work. We can design a bridge that withstands the required loads, an airplane that flies, a silicon chip that functions."