Whenever I think to myself or discuss with others, I make the case that generally tighter gun laws lead to more violence, and use praxeological arguments as well as empirical data (such as the fact that this country where I live has extremely strict gun laws and 50,000 homicides a year). But I was thinking: couldn't it be said that violence is a complex phenomena where no ceteris paribus situation or isolation of variables could ever occur, and that therefore no relationships of causality could be prooved or disprooved through empirical evidence? One would conlcude from this line of reasoning that empirical evidence can at best "illustrate" a conclusion arrived at via aprioristic reasoning.

At the same time, I suspect that trying to explain this to anyone I am trying to persuade could lead them to think I am full of shit and that I attempt to distance myself from "the grim facts of reality" by latching on to praxeological gobbledygook... so I would be compelled to not tell them everything I think.

Praxeological considerations, presuming any assumptions apply, would still influence action in a definite direction. The question is simply whether they are the prime or overriding factors, and how various idealogical and mechanical circumstances interact in the formation of values and rational action. Other processes may, of course, 'swamp' the deductive facts of economy, for example if a huge iridium asteroid struck india we may very well doubt if it would be able to significantly improve its division of labor even permitted entirely free markets and safety from all crime and fraud.