1. Science and pseudoscience ↑
"There is no such thing as philosophy-free science; there is only science whose philosophical baggage is taken on board without examination".
- Daniel Dennett, Darwin's Dangerous Idea, 1996.
Science has a massive impact on everyone. How we teach it, and what we decide to fund, can literally have life and death consequences for millions of people. This means it's vital that everyone has a good understanding of what science is and how it affects them.
If scientists want their claims to be taken more seriously than the claims of pseudoscience, for example, then they need to make sure that they, and their audience, know the difference between science and pseudoscience, and why this matters.
Although many scientists think about this and contribute to the discussion, it's not the job of scientists to define science. They are trained to be a scientist, in whatever capacity that entails, and that is what they are paid to do.
This is where philosophers come in, philosophers of science are paid to think about this, and almost any other subject that relates to science but doesn't full within the job description of scientists.
You may be wondering why philosophers are needed to do this, since scientists should be in the best position to define what they do. The problem is that the vast majority of scientists do not have any training in philosophy of science, and they would need to take the time to at least familiarise themselves with the subject before they could add anything new to it. Most scientists can simply not afford to take time out of their job to do this. Many would not want to. Many philosophers of science, on the other hand, have degrees in science related subjects before they study philosophy.
The almost complete separation of science and philosophy within academia is a fairly modern phenomenon. Philosophy existed before science as a way of understanding the external world. Before the philosophy of science, philosophers discussed what constitutes knowledge.
Some argued that only mathematics can tell us anything true about the world, as all our senses are fallible, and there's no way to know that the external world is real anyway.
Others argued that while this might give us the only true knowledge, this knowledge is not useful; it doesn't tell us anything about the world we live in. Whether the external world is real or not doesn't matter, because it has no consequence. Useful knowledge, they argued, comes from our senses. This is known as empirical knowledge.
What we now think of as science was once a form of empirical philosophy, known as natural philosophy. The term 'scientist' was not coined until the 1800s, and so the vast majority of scientists actually thought of themselves as natural philosophers, including Galileo Galilei and Isaac Newton.
Scientists no longer have to study any philosophy, and philosophy is not a part of the national curriculum in many countries. Science and philosophy are often thought of as being so completely different that many scientists have no idea why philosophy is important, or how it relates to them.
Philosophers' historic failure to anticipate Darwin is a severe indictment of philosophy. Happy Darwin Day!— Richard Dawkins (@RichardDawkins) February 12, 2014
In reality, scientists and philosophers of science tend to have the same goal, to find out the truth about the universe. Their approaches are different but complementary.
I have used the example of the definitions of science and pseudoscience above, because the deaths caused by climate change deniers and the Anti-Vaccination Movement clearly show the importance of having a good understanding of what science is, and why it should be taken seriously. Someone needs to play devil's advocate and thoroughly assess the scientific method, so that scientists know why it is reliable and how to defend it, and that's what philosophers do.
There are, however, many other things that philosophers of science are paid to think about, which everyone can benefit from, including the ethics that relate to science, and the meaning behind mathematical concepts.
2. Science and ethics ↑
"As our own species is in the process of proving, one cannot have superior science and inferior morals. The combination is unstable and self-destroying".
- Arthur C. Clarke, Voices From the Sky: Previews of the Coming Space Age, 1965.
We need people to be paid to think about ethics in general. There's no way to argue that we have human rights at all if we have no understanding of ethics.
Scientists can face a wide range of different ethical dilemmas, many of which can be reduced to concepts that philosophers have been thinking about for thousands of years, but as science presents us with the ability to do things we could never do before, and cultural norms change, it also presents new ethical challenges.
Philosophers of science stay up-to-date with their chosen scientific field, so they can anticipate these challenges and consider our options. Subjects like environmental ethics and biomedical ethics are especially important since they affect everyone.
3. Science and meaning ↑
"It would be possible to describe everything scientifically, but it would make no sense; it would be without meaning, as if you described a Beethoven symphony as a variation of wave pressure".
- Albert Einstein, quoted in Max Born's, Physik im Wandel meiner Zeit, 1966.
In some scientific subjects, the line between science and philosophy is ambiguous. This is especially true for quantum mechanics and Albert Einstein's theories of relativity. These theories present us with information that seems to defy common sense, and we struggle to express their meaning in any form but mathematics. It's the job of philosophers to consider whether there is any meaning beyond the mathematical, and what this could be.
In quantum mechanics, for example, a quantum state can be said to be in a 'superposition' of two states, until it is measured to be one or the other. A photon, for example, is thought of as having both wave and particle-like properties until you measure it with either a particle or wave detector, then it will be detected as either a wave or a particle. The act of measurement is said to make the superposition 'collapse'.
While this is a reasonable way to think about things if you just want to create experiments, make predictions, and generally get on with the job of being a quantum physicist, this interpretation has major philosophical problems that many scientists are curious about.
The term 'collapse', for example, cannot be a wholly accurate way of understanding the equations since there is nothing within quantum theory itself that explains it. There is nothing that mathematically defines what constitutes a 'measurement', and nothing to show where the line is drawn between the micro-world of quantum mechanics, and the macro-world we usually experience.
Quantum physicist Erwin Schrödinger developed his famous thought experiment - known as Schrödinger's cat - to illustrate these problems in 1935. Einstein agreed with Schrödinger, the collapse approach must be wrong, and philosophers of science have been discussing this problem ever since. This is despite the fact that scientists can keep working with the equations without needing this problem explained (in a similar way to how scientists in the 1500s could keep using the Ptolemaic system, which assumed the Sun orbits the Earth, because the mathematics worked despite its philosophical problems).
The two most popular solutions to the problems with the collapse approach to quantum mechanics are known as Bohmian mechanics and the Everett approach. The Everett approach takes the equations at face value, and so there is no distinction between the quantum world and the macro-world, and no 'collapse'. Instead, everything is always in a superpositional state, including people, and when someone measures the photon, they will detect it as both a wave and a particle.
They do not realise this because these two opposite states cannot exist in the same 'world', and so while they detect it as a wave in one world, they do not realise that they're also detecting it as a particle in another. This philosophical theory predicts the existence of parallel worlds, containing parallel copies of everyone, and scientists can now try to develop ways of proving whether or not they really exist.
This is just one example of philosophers of science trying to understand the meaning behind mathematical equations. Quantum mechanics also raises other philosophical questions regarding instantaneous action at a distance, teleportation, and the nature of human consciousness and individuality. Einstein's theories of relativity raise questions about the nature of spacetime, time travel, and our perception of time, as well as many other things, and the rest of science provides many more examples.
Even if most of these do not directly lead to new advancements in science, anyone who is curious may wish to read well thought-out answers to some of these questions. To use Einstein's example, some scientists may enjoy reading the mathematics that goes into a Beethoven symphony much more than they enjoy listening to it, but others feel the opposite way, and some enjoy both. The two viewpoints are not contradictory.
The philosophy of science can only expand upon our understanding of science. It can take nothing away from it.