Economics is definitely a social science. Even the most business-bro economist would agree.
But I would actually argue it is closer to physics than philosophy*. At the macroeconomics scale, there are very solid trends and predictions to be made with very solid hypotheses as to why they occur. And in a small town, you can generally get away with a lot of the higher level aspects of microeconomics and make solid predictions. Gas stations thrive on this shit. But high frequency trading, as well as sites that let individuals buy whatever stocks they want, really do narrow the region that can actually be considered either one and instead we are looking at having to apply “micro” concepts across entire countries worth of people.
Which… is physics. Drop a ball from a platform? You can math out when it will hit the ground to the nearest second pretty easily. Want to go milliseconds? Now you probably need to take into account air resistance, but you can probably do that with some not overly complex simulations and wind tunnel experiments. But as the height increases and you start putting a rocket engine on the back of that device, just doing a fluid mechanics simulation in your CAD program of choice stops being viable and you start needing to consider the underlying material properties and possibly even doing molecular dynamics simulations under the hood.
And… that is kind of where we are with economics. We have the high level math and simulations. Newton’s Three Laws have been discovered and people can get a long way. But nobody really understands the underlying causes well enough to find the economic equivalent of the Theory of Relativity. And nobody has figured out how to run simulations that can take into account… still only a subset of the variables at play.
Personally? I supported a decent number of simulations of population movement and the like as part of the covid efforts. I strongly suspect there is some underlying “science of why humans do the shit we do” that nobody has properly codified yet, and Economics is a subset of that. Because the more you look beyond ECON 101 level concepts, the more it is clear that there IS strong logic underneath and that a lot of “predictions based on trends” are very much “I predict that if we kick the ball at this angle with this much force, it will go that distance” levels of science. But there are so many factors involved that nobody understand how to account for.
*: Going by the modern definition rather than the historic one where most hard sciences were wrapped up in philosophy. One of the reasons we have “Doctorate of Philosophy” for physics and the like. … Which also speaks to how naive this post is