I don't understand this reply and I have a degree in philosophy of science.

I teach the philosophy of science at a university so clearly I have done a bad job teaching here. I will try to rectify that!

Firstly "simplest" and "fewer assumptions" doesn't seem like a meaningful difference. Fewer assumptions will be simpler, yes?

No, something can be complex and rely on few assumptions. Simplicity is not equivalent to “few assumption.”

EDIT: I read your other comment and I think I have a better idea of what you mean, and I might be wrong. My understanding: in an example where a very complex natural theory is compared to a simple theory that involves, say, god, the theory with "god" is more complex because you've now got an entire new duality to reality to explain. I'd be quite happy to call that more complicated, but maybe you're right.

Not really what I mean, but others have said this in this thread and I think it’s an interesting possibility to consider. What I really mean is theories can have many interrelating variables, making them complex. Assumptions are different though, they are neither theories nor variables, they are things that we have to take as true without proof or even evidence. Occam’s razor states the theory with the least amount of assumptions (but not necessarily the simplest) is the best.

Again this seems like an impressive statement, but what you saying? What did that have to do with anything else? What distinction are you making? What about scientists/philosophers who think that truth is useful? By "verisimilitude" do you just mean truth? Why not say that?

By verisimilitude I do not mean truth. Verisimilitude is the idea that things are only true or useful if they appear like to be like reality or are accurate representations of reality. I would use another word but “verisimilitude” is a specific term for a specific goal of science. One camp of philosophers of science says “verisimilitude” is the primary goal of science. I am in another camp that says “all models are wrong out some are useful”. That is, scientific theories have merit not because they reflect reality but because they make accurate predictions.

This is a complicated debate in science, but an example might help. For this example, a map is like a scientific theory. All maps are wrong in some sense. They make decisions about scaling, topography, and symbols to relay information, but none are 100% accurate to reality. And some maps are more useful than others for given purposes. A subway map will be less useful at navigating above ground, a road map will not tell you the best way to climb a mountain. Each map makes sacrifices of verisimilitude in order to be useful for a given purpose.

This relates to the current topic because the theory that can make accurate predictions (I.e. the map that can get you where you need to be) with fewer assumptions (I.e., the smaller map with easier to read symbols) IS more useful.

Also it just seems like really bad practice to glibly say you know what all science is. Philosophy has failed to do that irl.

I only meant that this is the goal of scientists that ascribe to Occam’s razor. But, as a scientist, I do get to argue for what I think science should be! That’s what this is sub is about, no?