Those who wish to defend libertarian free will over against a position like Calvinism often attempt to do so upon the basis of a strictly philosophical rather than exegetical basis. It is often asserted that determinism of any kind (which for the sake of argument includes Calvinism) precludes free will such that if we possess free will then indeterminism must be the case. Since there is libertarian free will indeterminism is true (and Calvinism is false).
Note that the inconsistency between libertarian free will and determinism is assumed. The assumption may be granted as definitional. Note also that libertarian free will is merely assumed rather than proven. One might just as easily assert that if Calvinism is true then libertarian free will is false. To be fair there are often arguments presented to try and support the premise that there is libertarian free will which usually take the form of a reductio ad absurdum. These arguments will not be discussed right now. Rather the concept of libertarian free will itself will be briefly examined.
Apparently libertarian free will by its very definition would have it that indeterminism obtains. However, if indeterminism is the case then the choices people make are not determined in any sense by the people who make them. Choices are therefore arbitrary. It may be objected that while choices are not determined they are still influenced by factors like the character or emotions of the agent making the choices and therefore they are not arbitrary.
However if the aforementioned factors (e.g. character, emotions) do not determine choices but only influence them then people might still make choices against their inclinations. If people can make choices against their inclinations then the objection is obsolete since the actual choices people make are still not necessarily affected in any sense by the people who make them. The same problem of arbitrariness mentioned before is still a problem.
Perhaps what the objector means to say is that our choices are delineated by the aforementioned influences. In this case a choice is made between options not excluded by the factors which “influence” the people making decisions. However again there is no relevant way in which the factors influence actual choices between the remaining options. Choices are apparently still separate from the people ‘making’ the choices and we are back to the same problem of arbitrariness.