Introduction to Francis Bacon (1561-1626)
Historical Context
 Latter part of the great age of exploration (The Americas)
 A period of transition: From an age of deference to authority to one of exploration,
invention, science, and erosion of religious authority (Protestant Revolution)
 Queen Mary’s (Catholic) execution of Protestants (around 300 burned at the stake) during
her short five-year reign.
 Active during the reigns of Queen Elizabeth (d. 1603) and King James I (became Lord
Chancellor)
 Roughly a contemporary of Galileo (1564-1642, Descartes (1596-1650), and Hobbes
(1588-1679)
Bacon’s Main Accomplishment and Influence:
 Refinement of scientific method (Instauratio Magna (The Great Renewal), containing
The Novum Organum (The New Instrument)
 His work lead to the establishment of research institutions, e.g., the Royal Society
(described in his New Atlantis), essential for the advancement of the sciences.
 Opposed dependence on tradition, authority, mystery, and superstition (but remained
religious)
 Studied Law
Bacon died in 1626 of pneumonia after conducting experiments with ice and chicken meat.
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Overview of main points of this presentation
The Idols (illusions) of the mind:
“For the mind of man is far from the nature of a clear and equal glass, wherein the beams of
things should reflect according to their true incidence, nay, it is rather like an enchanted glass,
full of superstition and imposture, if it be not delivered and reduced.” (The Advancement of
Learning)
Bacon’s Scientific Method
 *Bacon’s critique of Aristotelian science (Organum, Nova Organum), applies as well to
Renaissance alchemy, magic, and astrology: The ‘methods’ of these ‘disciplines’ utilize
occasional insights, but under investigation fail to reproduce results.
 *Does not favor empiricism over rationalism, but rather believes that both can fall short
and must be improved.
 Individual erudition must be abandoned in favor of collective research.
 *Bacon came to the fundamental insight that facts cannot be collected from nature, but
must be constituted by methodical procedures, which have to be put into practice by
scientists in order to determine their validity.
 *A new inductive method: Natural science should proceed, not from universal axioms,
but from particular observations, arriving at axioms (not beginning with them); not
simply by confirmation of hypotheses, but by negation and exclusion. See the example of
the tides, in the “Appendix” on “crucial instances,” which has been attached to our
reading selection (Book I of Nova Organum), but is actually from Book II. Also see the
“tables on heat,” available on the CS lecture website, not assigned, but discussed, below).
 Religion and science should be kept separate but are nevertheless complementary to each
other.
Main Points of the assigned texts:
Preface to Instauratio Magna (The Great Renewal) 1620
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Similar to Descartes, we need to “begin from correct foundations.” (How is he different
from Descartes?)
We are mostly ignorant because we depend on a “very deceptive and feeble method” (3).
“for the logic now in use . . . still falls a long way short of the subtlety of nature” (5).
Part of this is due to our own weaknesses (“The Idols,” see below)
We draw conclusions much too fast.
Note that The Great Renewal is supposed to contain six parts, just as God created the
world is six days and then rested on the seventh.
Wants to provide a “thread through the labyrinth” of nature, “from the first perceptions of
sense, [which have] to be made with a sure method,” right on through to the axioms (or
general truths and laws) (5).
“A true and lawful marriage between the empirical and rational faculties (whose sad
and unhappy divorce and separation have caused all the trouble in the human family” (7).
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Adam was forbidden to inquire into God’s will, but not into God’s intellect (created
nature).
Knowledge in the natural sciences is to be sought “for the uses and benefits of life, and to
improve and conduct it in charity (love).
“The Plan of the Work”
First part was not written.
Second is the New Organon (Books I and II)
Only some of the Third part was written.
Some of the Fifth.
The Sixth did not appear.
Bacon’s method outlined here will be explained in my section on the New Organon, below.
But the basic idea is:
 “And so the order of demonstration also is completely reversed. For the way the thing has
normally been done until now is to leap immediately from sense and particulars to the
most general propositions…”
 Whereas, induction should arrive at axioms gradually.
 Our method provides transparency.
 Experiments are aids to the senses, making the latter more reliable.
 Note, against Descartes: the intellect is more error prone than the senses. This will be
shown in the Idols.
 “Nature is conquered by obedience [to it]”
 The two goals of man, knowledge and power, a pair of twins, are really come to the same
thing…”
The New Organon (Book I)
Organon = ‘instrument’ and reflects Aristotle’s Organon, which contained his Prior Analytics,
Posterior Analytics, On Interpretation, Topics, Sophistical Refutations, and Categories. These
are also generally referred to by Bacon as “Aristotle’s Logic,” and are the targets of much of his
criticism.
*Why is the work written in aphorisms? They are attention grabbing. Succinct. Allowing
examination of the whole, part by part.
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“The cause and root of nearly all evils in the sciences is this—that while we falsely admire and
extol the powers of the human mind we neglect to seek for its true helps.”
Criticism of Aristotelian logic
XIV
The syllogism consists of propositions, propositions consist of words, words are symbols of
notions. Therefore if the notions themselves (which is the root of the matter) are confused and
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over hastily abstracted from the facts, there can be no firmness in the superstructure. Our only
hope therefore lies in a true induction. (3)
XXVI
The conclusions of human reason as ordinarily applied in matters of nature, I call for the sake of
distinction Anticipations of Nature (as a thing rash or premature). That reason which is elicited
from facts by a just and methodical process, I call Interpretation of Nature. (5)
To do this rightly, we need to dispel illusions.
THE IDOLS (p. 6)
XXXVIII
The idols and false notions which are now in possession of the human understanding, and have
taken deep root therein, not only so beset men's minds that truth can hardly find entrance, but
even after entrance is obtained, they will again in the very instauration of the sciences meet and
trouble us, unless men being forewarned of the danger fortify themselves as far as may be
against their assaults.
[Note that ‘human understanding’ refers to what we would now call our “cognitive ability,” our
ability to think. ‘The understanding’ is the name for that “faculty” or ability.]
XXXIX
There are four classes of Idols which beset men's minds. To these for distinction's sake I have
assigned names, calling the first class Idols of the Tribe, the second, Idols of the Cave; the third,
Idols of the Market Place; the fourth, Idols of the Theater.
Idols of the Tribe (of the human race)
Unlike other “empiricists” Bacon did not believe that the mind was a “blank slate” (tabla rasa)
at birth, such that knowledge of things consisted of what the mind merely received what it was
given. Rather:
“The understanding is like a false mirror, which, receiving rays irregularly, distorts and discolors
the nature of things by mingling its own nature with it.
How so?
Also: “on waxen tablets you cannot write anything new until you rub out the old. With the mind
it is not so; there you cannot rub out the old till you have written in the new” (Farrington 1964,
72).
Bacon’s own examples, Aph XLV
The human understanding is of its own nature prone to suppose the existence of more order and
regularity in the world than it finds…. Hence the fiction that all celestial bodies move in perfect
circles, spirals … being utterly rejected.
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[Can you think of any other examples?]
XLVI
[The mind tends to agree with what it already knows, and reject what it doesn’t]
The human understanding when it has once adopted an opinion (either as being the received
opinion or as being agreeable to itself) draws all things else to support and agree with it. And
though there be a greater number and weight of instances to be found on the other side, yet these
it either neglects and despises, or else by some distinction sets aside and rejects, in order that by
this great and pernicious predetermination the authority of its former conclusions may remain
inviolate. And therefore it was a good answer that was made by one who, when they showed him
hanging in a temple a picture of those who had paid their vows as having escaped shipwreck, and
would have him say whether he did not now acknowledge the power of the gods — "Aye," asked
he again, "but where are they painted that were drowned after their vows?" And such is the way
of all superstition, whether in astrology, dreams, omens, divine judgments, or the like;
it is the peculiar and perpetual error of the human intellect to be more moved and excited by
affirmatives than by negatives; whereas it ought properly to hold itself indifferently disposed
toward both alike. Indeed, in the establishment of any true axiom, the negative instance is the
more forcible of the two.
Deceptions of the affections
XLIX
Numberless, in short, are the ways, and sometimes imperceptible, in which the affections color
and infect the understanding.
Deceptions of the senses:
L
But by far the greatest hindrance and aberration of the human understanding proceeds from the
dullness, incompetency, and deceptions of the senses; in that things which strike the sense
outweigh things which do not immediately strike it, though they be more important. Hence it is
that speculation commonly ceases where sight ceases;
XLVII
The human understanding being unable to rest still seeks something prior in the order of nature.
And then it is that in struggling toward that which is further off it falls back upon that which is
nearer at hand, namely, on final causes, which have relation clearly to the nature of man rather
than to the nature of the universe; and from this source have strangely defiled philosophy.
[What are “final causes,” by the way?]
LI
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The human understanding is of its own nature prone to abstractions and gives a substance and
reality to things which are fleeting. But to resolve nature into abstractions is less to our purpose
than to dissect her into parts; as did the school of Democritus [atomism], which went further into
nature than the rest. Matter rather than forms should be the object of our attention, its
configurations and changes of configuration, and simple action, and law of action or motion; for
forms are figments of the human mind, unless you will call those laws of action forms.
[Aristotelian forms are figments; but Bacon’s forms are true natures and laws. See more about
forms in the section of the “Tables of Discovery,” below.]
The idols of the tribe, in sum:
The mind is prone to learn in twisted ways, because it is full of tendencies:
To seek regularity, though it is not.
To agree with what it already knows.
To reject the new and different, the threatening, the unpleasant.
To accept magical explanations.
To be moved by affirmatives.
To be moved by what strikes the emotions and senses sharply.
To seek purpose, where there is none.
Idols of the Cave (of the individual person)
XLII
For everyone (besides the errors common to human nature in general) has a cave or den of his
own, which refracts and discolors the light of nature, owing either to his own proper and peculiar
nature; or to his education and conversation with others; or to the reading of books, and the
authority of those whom he esteems and admires; or to the differences of impressions,
accordingly as they take place in a mind preoccupied and predisposed or in a mind indifferent
and settled; (7)
Also habit, and accident.
[Any examples you can think of?]
There is one principal and as it were radical distinction between different minds, in respect of
philosophy and the sciences, which is this: that some minds are stronger and apter to mark the
differences of things, others to mark their resemblances. The steady and acute mind can fix its
contemplations and dwell and fasten on the subtlest distinctions; the lofty and discursive mind
recognizes and puts together the finest and most general resemblances. Both kinds, however,
easily err in excess, by catching the one at gradations, the other at shadows.
Idols of the Marketplace (of our association with others)
lead men away into numberless empty controversies and idle fancies.
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LIX
But the Idols of the Market Place are the most troublesome of all — idols which have crept into
the understanding through the alliances of words and names. For men believe that their reason
governs words; but it is also true that words react on the understanding; and this it is that
has rendered philosophy and the sciences sophistical and inactive. Now words, being commonly
framed and applied according to the capacity of the vulgar, follow those lines of division which
are most obvious to the vulgar understanding. And whenever an understanding of greater
acuteness or a more diligent observation would alter those lines to suit the true divisions of
nature, words stand in the way and resist the change. . . . Yet even definitions cannot cure this
evil in dealing with natural and material things, since the definitions themselves consist of words,
and those words beget others. So that it is necessary to recur to individual instances, and those in
due series and order, as I shall say presently when I come to the method and scheme for the
formation of notions and axioms.
[Examples?]
LX
The idols imposed by words on the understanding are of two kinds. They are either names of
things which do not exist (for as there are things left unnamed through lack of observation, so
likewise are there names which result from fantastic suppositions and to which nothing in reality
corresponds), or they are names of things which exist, but yet confused and ill-defined, and
hastily and irregularly derived from realities.
Idols of the Theater (the theater of received science)
…all the received systems are but so many stage plays, representing worlds of their own creation
after an unreal and scenic fashion. … Neither again do I mean this only of entire systems, but
also of many principles and axioms in science, which by tradition, credulity, and negligence have
come to be received.
Three kinds of false philosophy: The Sophistical, the Empirical, and the Superstitious.
The Sophistical: Depends too much on Aristotelian science and fails to attend to experience.
What was wrong with Aristotelian science, anyway?
Aristotle held that certain “forms” could explain certain phenomena (not to be confused with
Bacon’s use of “form” as a law of nature (e.g., the form of heat, whose nature we will learn,
below).
Example 1: Why do things fall?
Because they have the form of gravitas.
What is gravitas?
That quality which makes things endeavor to reach their natural resting place (the center
of the Earth).
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But there is no explanation here of what gravitas consists of, how to measure it, or how to make
predictions.
Example 2: Why does alcohol make you sleepy?
Because it has soporific in it.
What is “soporific”?
That quality in a thing that makes you sleepy.
But this is no explanation. It says only that alcohol makes you sleepy because it has a sleepy
quality.
Aristotelian syllogism (“Logic”), understood as a deductive argument.
1. All things in nature have a purpose. (universal premise, presupposed)
2. Humans have teeth by nature.
(observation premise)
Therefore, teeth have a purpose.
(deductive conclusion)
How might Bacon question this argument?
Induction, on the other hand, begins with particular observations and then draws a general
conclusion.
1.
2.
3.
4.
5.
This barrel appears to be full of apples. I am told there are 100. (observation premise)
I have picked out five apples, each of which is rotten.
(observation premise)
Hypothesis: the next apple I pull out will be rotten
(hypothesis)
The next apple is rotten.
(observation)
Therefore, every apple in this barrel is rotten.
(general conclusion)
This is a weak inductive argument. We can make it stronger by increasing our sample size.
2. I have picked out 85 apples, all of which are rotten.
Therefore….
Is this strong enough?
Suppose I have picked out 99 rotten apples. Is the conclusion “every apple in this barrel is
rotten” guaranteed?
Bacon believed that:
1. Science could not begin with general premises (unless these were “common notions,” see
below).
2. A much stronger inductive method was required.
This leads to his criticisms of “the empirical school.”
The Empirical School (experimentation)
But the Empirical school of philosophy gives birth to dogmas more deformed and monstrous
than the Sophistical or Rational school. For it has its foundations not in the light of common
notions (which though it be a faint and superficial light, is yet in a manner universal, and has
reference to many things), but in the narrowness and darkness of a few experiments.
First, what are “common notions”? Euclid’s geometry:
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1. Things which equal the same thing also equal one another. (transitivity of identity)
2. If equals are added to equals, then the wholes are equal.
3. If equals are subtracted from equals, then the remainders are equal.
4. Things which coincide with one another equal one another.
5. The whole is greater than the part.
We can add:
6. A thing is identical to itself (principle of identity)
7. A thing cannot be and not be at the same time and in the same respect (principle of
non-contradiction)
The common notions do not require experimentation (they are known prior to experience).
They can be used in experiments, but they are not enough. Bacon held that experiments should
be repeatable, open to inspection, and should utilize any instruments that aid the senses
(microscopes, telescopes, etc.).
The inductive method also needs improvement (see Tables of Discovery in Book II).
Superstition
LXV
But the corruption of philosophy by superstition and an admixture of theology is far more widely
spread, and does the greatest harm, whether to entire systems or to their parts.
Examples: Pythagorean mathematics and mysticism
Aristotelian abstract forms and causes.
Don’t look for natural science in Genesis or Job.
“from this unwholesome mixture of things human and divine there arises not only a
fantastic philosophy but also a heretical religion. Very meet it is therefore that we be
sober-minded, and give to faith that only which is faith's.”
Also, avoid complete skepticism (acatalepsis), because it leads to dead ends.
Another example of superstition in science:
Kenelm Digby and “The Powder of Sympathy.” A powder used for healing wounds—applied not
to the wound, but to the weapon that caused it.
The recipe for the powder is: "take six or eight ounces of Roman vitriol [copper sulphate],
beat it very small in a mortar, sift it through a fine sieve when the sun enters Leo; keep it
in the heat of the sun and dry by night.”1
More on Bacon’s inductive method
See the document titled, “Bacon’s Inductive Method, example of heat,” on the CS
webpage for 203 lecture.
Bacon’s atomism: Matter in motion
1
Lewis Spense, Encyclopedia of Occultism and Parapsychology 1920, vol. 2, p. 725.
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“The force implanted by God in these first particles, form the multiplication thereof of all the
variety of things proceeds and is made up” (Bacon V [1889], 463).
Three main rules for the interpretation of nature:
 lay aside received opinion.
 refrain from highest generalizations (build up to them)
 Beware of “crucial instances”: If it seems there are only two alternatives, look carefully
for a third (see appendix at end of our reading—Book I of New Organon)
Basically: clear your mind of illusions and utilize a rigorous method.
Bacon’s optimism:
Who could imagine we would get silk from a worm, or navigation from a lodestone!
The possibilities are endless.
Bacon’s Ethics:
“Lastly, I would address one general admonition to all; that they consider what are the true ends
of knowledge, and that they seek it not either for pleasure of the mind, or for contention, or for
superiority to others, or for profit, or fame, or power, or any of these inferior things; but for the
benefit and use of life; and that they perfect and govern it in charity. For it was from the lust of
power that the angels fell, from lust of knowledge that man fell; but of charity there can be no
excess, neither did angel or man ever come in danger by it (Bacon IV [1901], 20f.: Instauratio
Magna, Preface).
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