Free will

Luther's well-known reply to Erasmus regarding free will is quite convoluted.  A few remarks.

Consider what Luther states here:

    "[O]ur aim is, simply, to investigate what ability 'free-will' has, in what respect it is the subject of Divine action and how it stands related to the grace of God.  If we know nothing of these things, we shall know nothing of Christianity, and shall be in worse case than any people on earth!" (The Bondage of the Will).

And one wonders why contemporary Protestants are obsessed with debates over free-will!  I take it that Luther considers his view of free-will as an essential item of faith, though many Protestants today would regard it as one of the non-essential, disputable points.  But Luther's claim seems way too strong in that if we do not appropriately understand free-will and its relation to God, then we know "nothing of Christianity".

I also enjoy comments by him such as this:

    "It is fundamentally necessary and wholesome for Christians to know that God foreknows nothing contingently, but that He foresees, purposes, and does all things according to His own immutable, eternal and infallible will.  This bombshell knocks 'free-will' flat, and utterly shatters it; so that those who want to assert it must either deny my bombshell, or pretend not to notice it, or find some other way of dodging it" (BotW).

I'm not sure what the "bombshell" is supposed to be since many free-will lovin' Christians will accept the claim in the first sentence.  As one interested in philosophy, I'm aching to write more about Luther's conception of human freedom, but since it doesn't pertain much to Reformation thought, I'll pass it by.

Though one thing I can't pass is Luther's impatience for subtle distinctions:

    "[T]hey maintained that all things take place necessarily, but by necessity of consequence, and not by necessity of the thing consequent...I shall not find it hard to show how unreal the distinction is... By necessity of consequence, they mean...[that] if God wills something, then it must needs be; but that which thus comes to be is something which of itself need not be...that is, it has no necessity in its own essential nature:  which is just to say that the thing done is not God Himself!" (BotW).

That's just a mess.  There is much confusion and conflation between de re and de dicto modal ascriptions.  The last line of this quote should be evidence of that!

Furthermore, to show how real the distinction between 'necessity of consequence' and 'necessity of consequent' is, let '[]' stand for 'it is necessary that'.  Then by 'necessity of consequence', we mean the kind of necessity that holds in the following:

    [1]  [](P --> Q).

So if God has infallible knowledge about the future, then:

   [2]  [](Yesterday God believed that R --> R).

However, the necessity of the thing consequent would yield:

  [3]  []R.

Given that [2] and [3] mean very different things, the distinction seems to be important, for the defender of free-will can accept [2] and yet reject [3].  Moreover, [2] does not yield [3] unless we add some further premise,

    [4] [](Yesterday God believed that R),

and some transfer principle along the lines of the following,

    [5] []P & [](P-->Q) |= []Q.

And [3] follows from [2],[4], and [5].  But defenders of free-will can accept God's infallible foreknowledge (thereby retaining [2]) and yet deny the fatalist conclusion [3].  For instance, those inspired by Boethius and Ockham can deny [4] (for different reasons), and those inspired by Molina can deny [5] (though I agree with those who think that Molinism does not entail the denial of [5]).

All this to say, Luther was being too hasty in his response to Erasmus.  Of course it may be true that humans do not have the kind of freedom that libertarians think we possess.  This is a difficult and complex issue, one that is worthy of philosophical inquiry; but I suspect that it does not bear much weight regarding our "knowledge of Christianity".