There are a few great arguments to bring to bear when you talk to statists that say X will not be funded without the state.
The first, and my favorite to bring out because of the reaction it gets is "So what?".
I usually follow by saying that if that is the case you have been OUTVOTED on the marketplace of dollars and ideas. If they are comitted to democracy and people would not voluntarily fund their activities or an activity they support, then how democratic is it to force this funding? If they really want something that would not be funded voluntarily to be funded by the state then logically they must advocate dictatorship.
Its also important to point out that the state does not create the wealth they redistribute. So whatever wealth goes into an obscure area of science must come from somewhere. The existence of the state does not add wealth to the pot that can be channelled into the activity they like, so whatever they want must come at the expense of things others want, and that they would pay for voluntarily.
One thing statists often say then is "There are some things more important than money". Thats a real howler, and you can point this out, considering their gripe was about money in the first place. If its really more important, why don't people do it for free? Why don't they do it for free?
I usually do not like to make the argument about the increase in wealth that the free market would create leading to all types of possibilities unitl later. I feel that making this argument early legitimizes their desire for whatever program or whatever they are advocating and I think the "so what" argument shakes this confidence. Statists are used to people catering to the legitimacy of their desire for whatever they advocate, and to refuse to do this puts them on the defensive in the argument.
"The evil that is in the world almost always comes of ignorance, and good intentions may do as much harm as malevolence if they lack understanding". - Albert Camus