Two problems here - firstly psychology is subject to falsification but falsification isn't a criterion for what is and isn't science. I know that's what popscience books teach and maybe a few first year science classes, but Popper's falsificationism was shown to be inadequate and in the real world scientists don't attempt to "falsify" theories in the way he suggested.

This is like me saying Newtonian mechanics is all there is to physics. First of all, Popper (who you brought up) is one small part of scientific statistical hypothesis testing which involves falsification. When you run repeats on an experiment you use null hypothesis testing. Secondly, parts of psychology and sociology can be falsified but there are plenty of claims in both fields which don't involve the scientific method because they contain non-empirical fields of research.

Secondly, you've just demonstrated that physics isn't a science, since string theory isn't empirical or falsifiable.

String theory is a pop.culture term. In science this is simply called Strings and involves mathematical conjectures about how physics might behave on quantum levels. It has never claimed to be empirical demonstrable but there is ways to falsify it that involves lack of symmetry breaking. Anyway you have invoked something that isn't scientific but is a tool (maths) used by scientists in prediction testing.

The correct response here is that one small research area doesn't disprove the scientific nature of the whole field.

It has never claimed to be scientific. It is maths. There is no evidence for it. People who study this get it. Its mathematical conjectures that deliver particle masses we predict to either find or not.

You've simply asserted this to be true without attempting to demonstrate it.

I demonstrated it with psychology and then gave you three areas of sociology which are problematic from an empirical point of view. The core problem is in its inability to make predictions at the level expected in science. This is because of measurements such as human bias which are fluid in the models themselves, even before the sociologist looks at the data.

Oh well, great argument. Your lack of substantive response however tells me that you don't know what you're talking about, and you were hoping that throwing big words out would help win an argument. When you realised that I understood what those words meant and explained how they didn't help your position, you had to slip back into "If I have to explain then you don't understand!" position.

I am not using big words. 'Applied science' is when someone takes something scientific and applies to doing something with it. Engineers do it. Psychologists do it. Sociologists do it. Its like applied maths, but the application is science to a topic, but isn't exclusive to it. Engineering for examples makes things we find useful. 'Useful' for humans, isn't a scientific term, as human subjectivity is involved in making this determination.

The extremists' beliefs largely revolve around political and philosophical issues, not religious ones. Didn't you read the article linked in the OP? They explain that the idea that religious beliefs cause their behavior is a myth and not supported by evidence.

I disagreed with the article. The question isn't answered by science. It is answered by psychology and sociology. Politics btw is a 'political science' in the same way that social issues are 'social sciences'. They simply use applied science in some of each piece of analysis they do. Not all is scientific, which is why it they aren't science... but are useful in answering the question being posed in the article.

Science can't 'falsify' the supernatural by its very methods. Science adopts the position of methodological naturalism, which means it only studies that which it can define as natural - the supernatural, by definition, cannot be defined as natural.

It can and does falsify all sorts of supernatural claims. The age of earth, epochs on this planet, the evolution of human beings and other organisms, the list goes on and on. The worldview of an extremist is simply not even closely resembling the scientific one any more. It is a full departure.

You should read the linked article, it explains why these kinds of religious beliefs don't actually cause terrorism. Your understanding of these issues seems about as rigorous as of charlatans like Sam Harris.

Again, someone who holds to a scientific worldview can't accept the underlying propositions posed by extremists. They are diametrically opposed. Hence why extremists undergo conditioning to enforce a worldview that isn't reality.

There's no such thing as the "dark ages", historians consider it to be a myth.

The dark ages was a time when scientific propositions were often met with hostile resistance by belief systems that were being challenged by them. During the middle ages this changed when old greek texts managed to get translated in Latin, which saw a scientific revolution from Galileo onwards.

Given that science has nothing to say about the existence of supernatural things, there's absolutely nothing that prevents them from being an extremist.

This is false. There are plenty of claims made by extremists that are scientific falsifiable and have been. Human origins. Earth origins. Mythological claims that are demonstrably false by looking at the actual evidence. The claims of extremists aren't all immune to scientific analysis. That is laughable at best. Do you really think biological evolution by natural selection doesn't have a serious impact on what extremists believe?

Again, look at Sam Harris - he's an extremist, or Donald Trump, both have described how they are willing to commit war crimes to defend their personal beliefs and kill people who have different beliefs to them. Neither are religious though.

Trump claims to be a Conservative Christian. Sam Harris writes books on Atheism and does radio interviews. He addresses issues that are political and philosophical hot potatoes and states what is science and what is not in his views. It isn't extreme to have dialogue which is all he asks for. However Sam Harris is just one point of view. The scientific method has produce a scientific worldview that can't be shared by extremists.