ALBERT EINSTEIN
REMARKS ON BERTRAND RUSSELL'S
THEORY OF KNOWLEDGE
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From The Philosophy of Bertrand Russell,
Vol. V of "The Library of Living Philosophers,"
edited by Paul Arthur Schilpp, 1944.
Translated from the original German by Paul
Arthur Schilpp.
Tudor Publishers. |
Albert Einstein
Remarks on Bertrand Russell's Theory of Knowledge
When the editor asked me to write something
about Bertrand Russell, my admiration and
respect for that author at once induced me
to say yes. I owe innumerably happy hours
to the reading of Russell's works, something
which I cannot say of any other contemporary
scientific writer, with the exception of
Thirsted Veiled. Soon, however, I discovered
that it is easier to give such a promise
than to fulfil it. I had promised to say
something about Russell as a philosopher
and epistemologist. After having in full
confidence begun with it, I quickly recognized
what a slippery field I had ventured upon,
having, due to lack of experience, until
now cautiously limited myself to the field
of physics. The present difficulties of his
science force the physicist to come to grips
with philosophical problems to a greater
degree than was the case with earlier generations.
Although I shall not speak here of those
difficulties, it was my concern with them,
more than anything else, which led me to
the position outlined in this essay.
In the evolution of philosophic thought through
the centuries, the following question has
played a major role: what knowledge is pure
thought able to supply independently of sense
perception? Is there any such knowledge?
If not, what precisely is the relation between
our knowledge and the raw material furnished
by sense impressions? An almost boundless
chaos of philosophical opinions corresponds
to these questions and to a few others intimately
connected with them. Nevertheless there is
visible in this process of relatively fruitless
but heroic endeavours a systematic trend
of development, namely, an increasing scepticism
concerning every attempt by means of pure
thought to learn something about the "objective
world," about the world of "things"
in contrast to the world of mere "concepts
and ideas." Be it said parenthetically
that, just as on the part of a real philosopher,
quotation marks are used here to introduce
an illegitimate concept, which the reader
is asked to permit for the moment, although
the concept is suspect in the eyes of the
philosophical police.
During philosophy's childhood it was rather
generally believed that it is possible to
find everything which can be known by means
of mere reflection. It was an illusion which
anyone can easily understand if, for a moment,
he dismisses what he has learned from later
philosophy and from natural science; he will
not be surprised to find that Plato ascribed
a higher reality to "ideas" than
to empirically experienceable things. Even
in Spinoza and as late as in Hegel this prejudice
was the vitalizing force which seems still
to have played the major role. Someone, indeed,
might even raise the question whether, without
something of this illusion, anything really
great can be achieved in the realm of philosophic
thought -- but we do not wish to ask this
question.
This more aristocratic illusion concerning
the unlimited penetrative power of thought
has as its counterpart the more plebeian
illusion of naive realism, according to which
things "are" as they are perceived
by us through our senses. This illusion dominates
the daily life of men and of animals; it
is also the point of departure in all of
the sciences, especially of the natural sciences.
These two illusions cannot be overcome independently.
The overcoming of naive realism has been
relatively simple. In his introduction to
his volume, An Inquiry Into Meaning and Truth,
Russell has characterized this process in
a marvellously concise fashion:
We all start from "naive realism,"
i. e., the doctrine that things are what
they seem. We think that grass is green,
that stones are hard, and that snow is cold.
But physics assures us that the greenness
of grass, the hardness of stones, and the
coldness of snow are not the greenness, hardness,
and coldness that we know in our experience,
but something very different. The observer,
when he seems to himself to be observing
a stone, is really, if physics is to be believed,
observing the effects of the stone upon himself.
Thus science seems to be at war with itself:
when it most means to be objective, it finds
itself plunged into subjectivity against
its will. Naive realism leads to physics,
and physics, if true, shows that naive realism
is false. Therefore naive realism, if true,
is false; therefore it is false. (pp. 14-15)
Apart from their masterful formulation these
lines say something which had never previously
occurred to me. For, superficially considered,
the mode of thought in Berkeley and Hume
seems to stand in contrast to the mode of
thought in the natural sciences. However,
Russell's just cited remark uncovers a connection:
if Berkeley relies upon the fact that we
do not directly grasp the "things"
of the external world through our senses,
but that only events causally connected with
the presence of "things" reach
our sense organs, then this is a consideration
which gets is persuasive character from our
confidence in the physical mode of thought.
For, if one doubts the physical mode of thought
in even its most general features, there
is no necessity to interpolate, between the
object and the act of vision, anything which
separates the object from the subject and
makes the "existence of the object"
problematical.
It was, however, the very same physical mode
of thought and its practical successes which
have shaken the confidence in the possibility
of understanding things and their relations
by means of purely speculative thought. Gradually
the conviction gained recognition that all
knowledge about things is exclusively a working-over
of the raw material furnished by the senses.
In this general (and intentionally somewhat
vaguely stated) form this sentence is probably
today commonly accepted. But this conviction
does not rest on the supposition that anyone
has actually proved the impossibility of
gaining knowledge of reality by means of
pure speculation, but rather upon the fact
that the empirical (in the above-mentioned
sense) procedure alone has shown its capacity
to be the source of knowledge. Galileo and
Hume first upheld this principle with full
clarity and decisiveness.
Hume saw that concepts which we must regard
as essential, such as, for example, causal
connection ,cannot be gained from material
given to us by the senses. This insight led
him to a sceptical attitude as concerns knowledge
of any kind. If one reads Hume's books, one
is amazed that many and sometimes even highly
esteemed philosophers after him have been
able to write so much obscure stuff and even
find grateful readers for it. Hume has permanently
influenced the development of the best philosophers
who came after him. One senses him in the
reading of Russell's philosophical analyses,
whose acumen and simplicity of expression
have often reminded me of Hume.
Man has an intense desire for assured knowledge.
That is why Hume's clear message seems crushing:
the sensory raw material, the only source
of our knowledge, through habit may lead
us to belief and expectation but not to the
knowledge and still less to the understanding
of lawful relations. Then Kant took the stage
with an idea which, though certainly untenable
in the form in which he put it, signified
a step towards the solution of Hume's dilemma:
whatever in knowledge is of empirical origin
is never certain (Hume). If, therefore, we
have definitely assured knowledge, it must
be grounded in reason itself. This is held
to be the case, for example, in the propositions
of geometry and in the principle of causality.
These and certain other types of knowledge
are, so to speak, a part of the implements
of thinking and therefore do not previously
have to be gained from sense data (i. e.,
they are a priori knowledge). Today everyone
knows, of course, that the mentioned concepts
contain nothing of the certainty, of the
inherent necessity, which Kant had attributed
to them. The following, however, appears
to me to be correct in Kant's statement of
the problem: in thinking we use, with a certain
"right," concepts to which there
is no access from the materials of sensory
experience, if the situation is viewed from
the logical point of view.
As a matter of fact, I am convinced that
even much more is to be asserted: the concepts
which arise in our thought and in our linguistic
expressions are all -- when viewed logically
-- the free creations of thought which cannot
inductively be gained from sense experiences.
This is not so easily noticed only because
we have the habit of combining certain concepts
and conceptual relations (propositions) so
definitely which certain sense experiences
that we do not become conscious of the gulf
-- logically unbridgeable -- which separates
the world of sensory experiences from the
world of concepts and propositions.
Thus, for example, the series of integers
is obviously an invention of the human mind,
a self-created tool which simplifies the
ordering of certain sensory experiences.
But there is no way in which this concept
could be made to grow, as it were, directly
out of sense experiences. It is deliberately
that I choose here the concept of a number,
because it belongs to the pre-scientific
thinking and because, in spite of that fact,
its constructive character is still easily
recognizable. The more, however ,we turn
to the most primitive concepts of everyday
life, the more difficult it becomes amidst
the mass of inveterate habits to recognize
the concept as an independent creation of
thinking. It was thus that the fateful conception
-- fateful, that is to say, for an understanding
of the here-existing conditions -- could
arise, according to which the concepts originate
from experience by way of "abstraction,"
i. e., through omission of a part of its
content. I want to indicate now why this
conception appears to me to be so fateful.
As soon as one is at home in Hume's critique
one is easily led to believe that all those
concepts and propositions which cannot be
deduced from the sensory raw material are,
on account of their "metaphysical"
character, to be removed from thinking. For
all thought acquires material content only
through its relationship with that sensory
material. This latter proposition I take
to be entirely true; but I hold the prescription
for thinking which is grounded on this proposition
to be false. For this claim -- if only carried
through consistently -- absolutely excludes
thinking of any kind as "metaphysical."
In order that thinking might not degenerate
into "metaphysics," or into empty
talk, it is only necessary that enough propositions
of the conceptual system be firmly enough
connected with sensory experiences and that
the conceptional system, in view of its task
of ordering and surveying sense experience,
should show as much unity and parsimony as
possible. Beyond that, however, the "system"
is (as regards logic) a free play with symbols
according to (logically) arbitrarily given
rules of the game. All this applies as much
(and in the same manner) to the thinking
in daily life as to the more consciously
and systematically constructed thinking of
the sciences.
It will now be clear what is meant if I make
the following statement: by his clear critique
Hume did not only advance philosophy in a
decisive way but also -- though through no
fault of his -- created a danger for philosophy
tin that, following his critique, a fateful
"fear of metaphysics" arose which
has come to be a malady of contemporary empiricistic
philosophizing; this malady is the counterpart
to that earlier philosophizing in the clouds,
which thought it could neglect and dispense
with what was given by the senses.
No matter how much one may admire the acute
analysis which Russell has given us in his
latest book on Meaning and Truth, it still
seems to me that even there the specter of
the metaphysical fear has caused some damage.
For this fear seems to me, for example, to
be the cause for conceiving of the "thing"
as a "bundle of qualities," such
that the "qualities" are to be
taken from the sensory raw material. Now
the fact that two things are said to be one
and the same thing, if they coincide in all
qualities, forces one to consider the geometrical
relations between things as belonging to
their qualities. (Otherwise one is forced
to look upon the Afield Tower in Paris and
a New York skyscraper as "the same thing.")*
However, I see no "metaphysical"
danger in taking the thing (the object in
the sense of physics) as an independent concept
into the system together with the proper
spatio-temporal structure.
In view of these endeavours I am particularly
pleased to note that, in the last chapter
of the book, it finally turns out that one
can, after all, not get along without "metaphysics."
The only thing to which I take exception
there is the bad intellectual conscience
which shines through between the lines.
* Compare Russell's An Inquiry Into Meaning
and Truth, 119-120, chapter on "Proper
Names."
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