which calls in question the general applicability of the law of
causation. He maintains that every event, and more particularly every
mental event, embodies so much of the past that it could not possibly
have occurred at any earlier time, and is therefore necessarily quite
different from all previous and subsequent events. If, for example, I
read a certain poem many times, my experience on each occasion is
modified by the previous readings, and my emotions are never repeated
exactly. The principle of causation, according to him, asserts that the
same cause, if repeated, will produce the same effect. But owing to
memory, he contends, this principle does not apply to mental events.
What is apparently the same cause, if repeated, is modified by the mere
fact of repetition, and cannot produce the same effect. He infers that
every mental event is a genuine novelty, not predictable from the past,
because the past contains nothing exactly like it by which we could
imagine it. And on this ground he regards the freedom of the will as
unassailable.
Bergson's contention has undoubtedly a great deal of truth, and I have
no wish to deny its importance. But I do not think its consequences are
quite what he believes them to be. It is not necessary for the
determinist to maintain that he can foresee the whole particularity of
the act which will be performed. If he could foresee that A was going to
murder B, his foresight would not be invalidated by the fact that he
could not know all the infinite complexity of A's state of mind in
committing the murder, nor whether the murder was to be performed with a
knife or with a revolver. If the _kind_ of act which will be performed
can be foreseen within narrow limits, it is of little practical interest
that there are fine shades which cannot be foreseen. No doubt every time
the story of the grouse in the gun-room is told, there will be slight
differences due to increasing habitualness, but they do not invalidate
the prediction that the story will be told. And there is nothing in
Bergson's argument to show that we can never predict what _kind_ of act
will be performed.
Again, his statement of the law of causation is inadequate. The law does
not state merely that, if the _same_ cause is repeated, the _same_
effect will result. It states rather that there is a constant relation
between causes of certain kinds and effects of certain kinds. For
example, if a body falls freely, there is a constant relation between
the height through which it falls and the time it takes in falling. It
is not necessary to have a body fall through the _same_ height which has
been previously observed, in order to be able to foretell the length of
time occupied in falling. If this were necessary, no prediction would be
possible, since it would be impossible to make the height exactly the
same on two occasions. Similarly, the attraction which the sun will
exert on the earth is not only known at distances for which it has been
observed, but at all distances, because it is known to vary as the
inverse square of the distance. In fact, what is found to be repeated is
always the _relation_ of cause and effect, not the cause itself; all
that is necessary as regards the cause is that it should be of the same
_kind_ (in the relevant respect) as earlier causes whose effects have
been observed.
Another respect in which Bergson's statement of causation is inadequate
is in its assumption that the cause must be _one_ event, whereas it may
be two or more events, or even some continuous process. The substantive
question at issue is whether mental events are determined by the past.
Now in such a case as the repeated reading of a poem, it is obvious that
our feelings in reading the poem are most emphatically dependent upon
the past, but not upon one single event in the past. All our previous
readings of the poem must be included in the cause. But we easily
perceive a certain law according to which the effect varies as the
previous readings increase in number, and in fact Bergson himself
tacitly assumes such a law. We decide at last not to read the poem
again, because we know that this time the effect would be boredom. We
may not know all the niceties and shades of the boredom we should feel,
but we know enough to guide our decision, and the prophecy of boredom is
none the less true for being more or less general. Thus the kinds of
cases upon which Bergson relies are insufficient to show the
impossibility of prediction in the only sense in which prediction has
practical or emotional interest. We may therefore leave the
consideration of his arguments and address ourselves to the problem
directly.
The law of causation, according to which later events can theoretically
be predicted by means of earlier events, has often been held to be _a
priori_, a necessity of thought, a category without which science would
be impossible. These claims seem to me excessive. In certain directions
the law has been verified empirically, and in other directions there is
no positive evidence against it. But science can use it where it has
been found to be true, without being forced into any assumption as to
its truth in other fields. We cannot, therefore, feel any _a priori_
certainty that causation must apply to human volitions.
The question how far human volitions are subject to causal laws is a
purely empirical one. Empirically it seems plain that the great majority
of our volitions have causes, but it cannot, on this account, be held
necessarily certain that all have causes. There are, however, precisely
the same kinds of reasons for regarding it as probable that they all
have causes as there are in the case of physical events.
We may suppose--though this is doubtful--that there are laws of
correlation of the mental and the physical, in virtue of which, given
the state of all the matter in the world, and therefore of all the
brains and living organisms, the state of all the minds in the world
could be inferred, while conversely the state of all the matter in the
world could be inferred if the state of all the minds were given. It is
obvious that there is _some_ degree of correlation between brain and
mind, and it is impossible to say how complete it may be. This, however,
is not the point which I wish to elicit. What I wish to urge is that,
even if we admit the most extreme claims of determinism and of
correlation of mind and brain, still the consequences inimical to what
is worth preserving in free will do not follow. The belief that they
follow results, I think, entirely from the assimilation of causes to
volitions, and from the notion that causes _compel_ their effects in
some sense analogous to that in which a human authority can compel a man
to do what he would rather not do. This assimilation, as soon as the
true nature of scientific causal laws is realised, is seen to be a sheer
mistake. But this brings us to the second of the two questions which we
raised in regard to free will, namely, whether, assuming determinism,
our actions can be in any proper sense regarded as compelled by outside
forces.
(2) _Are human actions subject to an external compulsion?_ We have, in
deliberation, a subjective sense of freedom, which is sometimes alleged
against the view that volitions have causes. This sense of freedom,
however, is only a sense that we can choose which we please of a number
of alternatives: it does not show us that there is no causal connection
between what we please to choose and our previous history. The supposed
inconsistency of these two springs from the habit of conceiving causes
as analogous to volitions--a habit which often survives unconsciously in
those who intend to conceive causes in a more scientific manner. If a
cause is analogous to a volition, outside causes will be analogous to an
alien will, and acts predictable from outside causes will be subject to
compulsion. But this view of cause is one to which science lends no
countenance. Causes, we have seen, do not _compel_ their effects, any
more than effects _compel_ their causes. There is a mutual relation, so
that either can be inferred from the other. When the geologist infers
the past state of the earth from its present state, we should not say
that the present state _compels_ the past state to have been what it
was; yet it renders it necessary as a consequence of the data, in the
only sense in which effects are rendered necessary by their causes. The
difference which we _feel_, in this respect, between causes and effects
is a mere confusion due to the fact that we remember past events but do
not happen to have memory of the future.
The apparent indeterminateness of the future, upon which some advocates
of free will rely, is merely a result of our ignorance. It is plain that
no desirable kind of free will can be dependent simply upon our
ignorance; for if that were the case, animals would be more free than
men, and savages than civilised people. Free will in any valuable sense
must be compatible with the fullest knowledge. Now, quite apart from any
assumption as to causality, it is obvious that complete knowledge would
embrace the future as well as the past. Our knowledge of the past is not
wholly based upon causal inferences, but is partly derived from memory.
It is a mere accident that we have no memory of the future. We might--as
in the pretended visions of seers--see future events immediately, in the
way in which we see past events. They certainly will be what they will
be, and are in this sense just as determined as the past. If we saw
future events in the same immediate way in which we see past events,
what kind of free will would still be possible? Such a kind would be
wholly independent of determinism: it could not be contrary to even the
most entirely universal reign of causality. And such a kind must contain
whatever is worth having in free will, since it is impossible to believe
that mere ignorance can be the essential condition of any good thing.
Let us therefore imagine a set of beings who know the whole future with
absolute certainty, and let us ask ourselves whether they could have
anything that we should call free will.
Such beings as we are imagining would not have to wait for the event in
order to know what decision they were going to adopt on some future
occasion. They would know now what their volitions were going to be. But
would they have any reason to regret this knowledge? Surely not, unless
the foreseen volitions were in themselves regrettable. And it is less
likely that the foreseen volitions would be regrettable if the steps
which would lead to them were also foreseen. It is difficult not to
suppose that what is foreseen is fated, and must happen however much it
may be dreaded. But human actions are the outcome of desire, and no
foreseeing can be true unless it takes account of desire. A foreseen
volition will have to be one which does not become odious through being
foreseen. The beings we are imagining would easily come to know the
causal connections of volitions, and therefore their volitions would be
better calculated to satisfy their desires than ours are. Since
volitions are the outcome of desires, a prevision of volitions contrary
to desires could not be a true one. It must be remembered that the
supposed prevision would not create the future any more than memory
creates the past. We do not think we were necessarily not free in the
past, merely because we can now remember our past volitions. Similarly,
we might be free in the future, even if we could now see what our future
volitions were going to be. Freedom, in short, in any valuable sense,
demands only that our volitions shall be, as they are, the result of our
own desires, not of an outside force compelling us to will what we would
rather not will. Everything else is confusion of thought, due to the
feeling that knowledge _compels_ the happening of what it knows when
this is future, though it is at once obvious that knowledge has no such
power in regard to the past. Free will, therefore, is true in the only
form which is important; and the desire for other forms is a mere effect
of insufficient analysis.
* * * * *
What has been said on philosophical method in the foregoing lectures has
been rather by means of illustrations in particular cases than by means
of general precepts. Nothing of any value can be said on method except
through examples; but now, at the end of our course, we may collect
certain general maxims which may possibly be a help in acquiring a
philosophical habit of mind and a guide in looking for solutions of
philosophic problems.
Philosophy does not become scientific by making use of other sciences,
in the kind of way in which (_e.g._) Herbert Spencer does. Philosophy
aims at what is _general_, and the special sciences, however they may
_suggest_ large generalisations, cannot make them certain. And a hasty
generalisation, such as Spencer's generalisation of evolution, is none
the less hasty because what is generalised is the latest scientific
theory. Philosophy is a study apart from the other sciences: its results
cannot be established by the other sciences, and conversely must not be
such as some other science might conceivably contradict. Prophecies as
to the future of the universe, for example, are not the business of
philosophy; whether the universe is progressive, retrograde, or
stationary, it is not for the philosopher to say.
In order to become a scientific philosopher, a certain peculiar mental
discipline is required. There must be present, first of all, the desire
to know philosophical truth, and this desire must be sufficiently strong
to survive through years when there seems no hope of its finding any
satisfaction. The desire to know philosophical truth is very rare--in
its purity, it is not often found even among philosophers. It is
obscured sometimes--particularly after long periods of fruitless
search--by the desire to _think_ we know. Some plausible opinion
presents itself, and by turning our attention away from the objections
to it, or merely by not making great efforts to find objections to it,
we may obtain the comfort of believing it, although, if we had resisted
the wish for comfort, we should have come to see that the opinion was
false. Again the desire for unadulterated truth is often obscured, in
professional philosophers, by love of system: the one little fact which
will not come inside the philosopher's edifice has to be pushed and
tortured until it seems to consent. Yet the one little fact is more
likely to be important for the future than the system with which it is
inconsistent. Pythagoras invented a system which fitted admirably with
all the facts he knew, except the incommensurability of the diagonal of
a square and the side; this one little fact stood out, and remained a
fact even after Hippasos of Metapontion was drowned for revealing it. To
us, the discovery of this fact is the chief claim of Pythagoras to
immortality, while his system has become a matter of merely historical
curiosity.[57] Love of system, therefore, and the system-maker's vanity
which becomes associated with it, are among the snares that the student
of philosophy must guard against.
[57] The above remarks, for purposes of illustration, adopt one of
several possible opinions on each of several disputed points.
The desire to establish this or that result, or generally to discover
evidence for agreeable results, of whatever kind, has of course been the
chief obstacle to honest philosophising. So strangely perverted do men
become by unrecognised passions, that a determination in advance to
arrive at this or that conclusion is generally regarded as a mark of
virtue, and those whose studies lead to an opposite conclusion are
thought to be wicked. No doubt it is commoner to wish to arrive at an
agreeable result than to wish to arrive at a true result. But only those
in whom the desire to arrive at a _true_ result is paramount can hope to
serve any good purpose by the study of philosophy.
But even when the desire to know exists in the requisite strength, the
mental vision by which abstract truth is recognised is hard to
distinguish from vivid imaginability and consonance with mental habits.
It is necessary to practise methodological doubt, like Descartes, in
order to loosen the hold of mental habits; and it is necessary to
cultivate logical imagination, in order to have a number of hypotheses
at command, and not to be the slave of the one which common sense has
rendered easy to imagine. These two processes, of doubting the familiar
and imagining the unfamiliar, are correlative, and form the chief part
of the mental training required for a philosopher.
The naive beliefs which we find in ourselves when we first begin the
process of philosophic reflection may turn out, in the end, to be almost
all capable of a true interpretation; but they ought all, before being
admitted into philosophy, to undergo the ordeal of sceptical criticism.
Until they have gone through this ordeal, they are mere blind habits,
ways of behaving rather than intellectual convictions. And although it
may be that a majority will pass the test, we may be pretty sure that
some will not, and that a serious readjustment of our outlook ought to
result. In order to break the dominion of habit, we must do our best to
doubt the senses, reason, morals, everything in short. In some
directions, doubt will be found possible; in others, it will be checked
by that direct vision of abstract truth upon which the possibility of
philosophical knowledge depends.
At the same time, and as an essential aid to the direct perception of
the truth, it is necessary to acquire fertility in imagining abstract
hypotheses. This is, I think, what has most of all been lacking hitherto
in philosophy. So meagre was the logical apparatus that all the
hypotheses philosophers could imagine were found to be inconsistent with
the facts. Too often this state of things led to the adoption of heroic
measures, such as a wholesale denial of the facts, when an imagination
better stocked with logical tools would have found a key to unlock the
mystery. It is in this way that the study of logic becomes the central
study in philosophy: it gives the method of research in philosophy, just
as mathematics gives the method in physics. And as physics, which, from
Plato to the Renaissance, was as unprogressive, dim, and superstitious
as philosophy, became a science through Galileo's fresh observation of
facts and subsequent mathematical manipulation, so philosophy, in our
own day, is becoming scientific through the simultaneous acquisition of
new facts and logical methods.
In spite, however, of the new possibility of progress in philosophy, the
first effect, as in the case of physics, is to diminish very greatly the
extent of what is thought to be known. Before Galileo, people believed
themselves possessed of immense knowledge on all the most interesting
questions in physics. He established certain facts as to the way in
which bodies fall, not very interesting on their own account, but of
quite immeasurable interest as examples of real knowledge and of a new
method whose future fruitfulness he himself divined. But his few facts
sufficed to destroy the whole vast system of supposed knowledge handed
down from Aristotle, as even the palest morning sun suffices to
extinguish the stars. So in philosophy: though some have believed one
system, and others another, almost all have been of opinion that a great
deal was known; but all this supposed knowledge in the traditional
systems must be swept away, and a new beginning must be made, which we
shall esteem fortunate indeed if it can attain results comparable to
Galileo's law of falling bodies.
By the practice of methodological doubt, if it is genuine and prolonged,
a certain humility as to our knowledge is induced: we become glad to
know _anything_ in philosophy, however seemingly trivial. Philosophy has
suffered from the lack of this kind of modesty. It has made the mistake
of attacking the interesting problems at once, instead of proceeding
patiently and slowly, accumulating whatever solid knowledge was
obtainable, and trusting the great problems to the future. Men of
science are not ashamed of what is intrinsically trivial, if its
consequences are likely to be important; the _immediate_ outcome of an
experiment is hardly ever interesting on its own account. So in
philosophy, it is often desirable to expend time and care on matters
which, judged alone, might seem frivolous, for it is often only through
the consideration of such matters that the greater problems can be
approached.
When our problem has been selected, and the necessary mental discipline
has been acquired, the method to be pursued is fairly uniform. The big
problems which provoke philosophical inquiry are found, on examination,
to be complex, and to depend upon a number of component problems,
usually more abstract than those of which they are the components. It
will generally be found that all our initial data, all the facts that we
seem to know to begin with, suffer from vagueness, confusion, and
complexity. Current philosophical ideas share these defects; it is
therefore necessary to create an apparatus of precise conceptions as
general and as free from complexity as possible, before the data can be
analysed into the kind of premisses which philosophy aims at
discovering. In this process of analysis, the source of difficulty is
tracked further and further back, growing at each stage more abstract,
more refined, more difficult to apprehend. Usually it will be found that
a number of these extraordinarily abstract questions underlie any one of
the big obvious problems. When everything has been done that can be done
by method, a stage is reached where only direct philosophic vision can
carry matters further. Here only genius will avail. What is wanted, as a
rule, is some new effort of logical imagination, some glimpse of a
possibility never conceived before, and then the direct perception that
this possibility is realised in the case in question. Failure to think
of the right possibility leaves insoluble difficulties, balanced
arguments pro and con, utter bewilderment and despair. But the right
possibility, as a rule, when once conceived, justifies itself swiftly by
its astonishing power of absorbing apparently conflicting facts. From
this point onward, the work of the philosopher is synthetic and
comparatively easy; it is in the very last stage of the analysis that
the real difficulty consists.
Of the prospect of progress in philosophy, it would be rash to speak
with confidence. Many of the traditional problems of philosophy, perhaps
most of those which have interested a wider circle than that of
technical students, do not appear to be soluble by scientific methods.
Just as astronomy lost much of its human interest when it ceased to be
astrology, so philosophy must lose in attractiveness as it grows less
prodigal of promises. But to the large and still growing body of men
engaged in the pursuit of science--men who hitherto, not without
justification, have turned aside from philosophy with a certain
contempt--the new method, successful already in such time-honoured
problems as number, infinity, continuity, space and time, should make an
appeal which the older methods have wholly failed to make. Physics, with
its principle of relativity and its revolutionary investigations into
the nature of matter, is feeling the need for that kind of novelty in
fundamental hypotheses which scientific philosophy aims at facilitating.
The one and only condition, I believe, which is necessary in order to
secure for philosophy in the near future an achievement surpassing all
that has hitherto been accomplished by philosophers, is the creation of
a school of men with scientific training and philosophical interests,
unhampered by the traditions of the past, and not misled by the literary
methods of those who copy the ancients in all except their merits.
INDEX
Absolute, 6, 39.
Abstraction, principle of, 42, 124 ff.
Achilles, Zeno's argument of, 173.
Acquaintance, 25, 144.
Activity, 224 ff.
Allman, 161 n.
Analysis, 185, 204, 211, 241.
legitimacy of, 150.
Anaximander, 3.
Antinomies, Kant's, 155 ff.
Aquinas, 10.