Phi 272 F06, reading guide

Carnap’s title for this chapter could be a little misleading. He really does not have too much to say about the topic of determinism in its own right (he will have more to say in the last part of the book). His real concern in this chapter is the implications of determinism for the existence of free will.

The core of the chapter is Carnap’s presentation of his own position regarding these implications. He indicates some alternatives to it and you can probably guess some others, so let me just provide a framework for classifying some positions regarding the issue.

Incompatibilism. This is the view that determinism is incompatible with free will. A proponent of this view might (i) accept determinism and reject the existence of free will (a view sometimes called hard determinism) or (ii) accept the existence of free will and reject determinism (see below for a famous ancient example of this view). Of course, it would be possible to reject both free will and determinism but someone holding such a view is probably not interested in the relation between the two. In any case, any view rejecting determinism is often called indeterminism.

Compatibilism. Proponents of this view hold that the freedom of will, correctly understood, is compatible with the determinism. People who agree about this may disagree about other issues. For example, a compatibilist might hold that what makes an action free can be understood in physical terms—that is, that it would be (in principle) possible to define freedom using ideas from the natural science. This view would be a sort of reductionism concerning freedom. A different sort of compatibilist might deny this and say that the distinction between those causally determined events that are free actions and those that are not cannot be made in physical terms.

According to one way of understanding him, Immanuel Kant (1724-1804) held that natural science and morality provided two alternative ways of thinking about the world. From the point of view of natural science, all events are causally determined and, from the point of view of morality, there are free actions. This can be seen as a sort of non-reductionist compatibilism; but, if these two ways of thinking about the world are sufficiently independent of each other, they may have too little relation for the term “compatible” to be very appropriate, and a position like the one Kant has (on this interpretation of him) could be seen as a third alternative in addition to incompatibilism and compatibilism.

Think which of these positions you are most sympathetic to, and think about the reasons you would offer to explain why you find that position the most attractive.

Epicurus (341-270) modified the atomism of the 5^th century Greek philosophers Leucippus and Democritus by introducing a degree of indeterminism, and he cited this as the source of freedom of will. The following is a quotation from De Rerum Natura (“Of the Nature of Things”) by the Roman poet Lucretius, who lived in the first half of the 1^st century B.C.E. and whose views closely follow those of Epicurus (so far as people can tell from reports in other ancient sources—Epicurus’ own works did not survive).

In these affairs
We wish thee also well aware of this:
The atoms, as their own weight bears them down
Plumb through the void, at scarce determined times,
In scarce determined places, from their course
Decline a little—call it, so to speak,
Mere changed trend. For were it not their wont
Thuswise to swerve, down would they fall, each one,
Like drops of rain, through the unbottomed void;
And then collisions ne’er could be nor blows
Among the primal elements; and thus
Nature would never have created aught.

…

Again, if ev’r all motions are co-linked,
And from the old ever arise the new
In fixed order, and primordial seeds
Produce not by their swerving some new start
Of motion to sunder the covenants of fate,
That cause succeed not cause from everlasting,
Whence this free will for creatures o’er the lands,
Whence is it wrested from the fates,—this will
Whereby we step right forward where desire
Leads each man on, whereby the same we swerve
In motions, not as at some fixed time,
Nor at some fixed line of space, but where
The mind itself has urged? For out of doubt
In these affairs ’tis each man’s will itself
That gives the start, and hence throughout our limbs
Incipient motions are diffused. Again,
Dost thou not see, when, at a point of time,
The bars are opened, how the eager strength
Of horses cannot forward break as soon
As pants their mind to do? For it behooves
That all the stock of matter, through the frame,
Be roused, in order that, through every joint,
Aroused, it press and follow mind’s desire;
So thus thou seest initial motion’s gendered
From out the heart, aye, verily, proceeds
First from the spirit’s will, whence at the last
’Tis given forth through joints and body entire.
Quite otherwise it is, when forth we move,
Impelled by a blow of another’s mighty powers
And mighty urge; for then ’tis clear enough
All matter of our total body goes,
Hurried along, against our own desire—
Until the will has pulled upon the reins
And checked it back, throughout our members all;
At whose arbitrament indeed sometimes
The stock of matter’s forced to change its path,
Throughout our members and throughout our joints,
And, after being forward cast, to be
Reined up, whereat it settles back again.
So seest thou not, how, though external force
Drive men before, and often make them move,
Onward against desire, and headlong snatched,
Yet is there something in these breasts of ours
Strong to combat, strong to withstand the same?—
Wherefore no less within the primal seeds
Thou must admit, besides all blows and weight,
Some other cause of motion, whence derives
This power in us inborn, of some free act.—
Since naught from nothing can become, we see.
For weight prevents all things should come to pass
Through blows, as ’twere, by some external force;
But that man’s mind itself in all it does
Hath not a fixed necessity within,
Nor is not, like a conquered thing, compelled
To bear and suffer,—this state comes to man
From that slight swervement of the elements
In no fixed line of space, in no fixed time.

Lucretius, Of The Nature of Things
William Ellery Leonard, tr.
bk. II, ll. 216-224, 251-294)