2. Euclid of Alexandria
Alexandria Death of Alexander the
Great
Ptolemies
Museum and Library
Ptolemy II
Euclid
Elements (Stoichia)
Obscure!!!
Ptolemy I
3. Euclid of Alexandria
Lost works
DID YOU KNOW THAT!!!
Of what Euclid
wrote, more than half
has been lost!!!
Treatise on conics in four
books
Treatise on Solid Loci (the
Greek name for the conic
sections)
Surface Loci
Pseudaria (or fallacies)
three books on Porisms
the loss of Euclidean
Porisms Pappus
Porism is intermediate between a theorem, in
which something is proposed for demonstration
, and a problem, in which something is proposed
for construction.
A proposition in which one
determines a relationship
between known and variable or
undetermined quantities
4. Euclid of Alexandria
Extant works
Elements
Data
Division of Figures
Phaenomena
Optics
Optical Phenomena
optics
catoptrics
dioptrics
The geometry of direct
vision
The geometry of refracted
rays
The geometry of reflected
rays
5. Euclid of Alexandria
Extant works
Euclid’s Optics “emission” theory of visionEuclidean Division of
Figures
Arabic Scholars
Arabic Translations
Latin
Current modern languages
6. Euclidean Division of
Figures
Euclid of Alexandria
Includes a collection of
thirty-six propositions
concerning the
division of plane
configurations
Proposition 1
Calls for the construction
of a straight line that
shall be parallel to the
base of a triangle and
shall divide the triangle
into two equal areas.
Proposition 6
Call for the division of a
parallelogram into two
equal parts by a line
drawn through a given
point on one of the sides
or (proposition 10)
through a given point
outside the
parallelogram.
Final Preposition (36)
Asks for the division of a
quadrilateral in a given
ratio by a line through a
point on one of the sides
of the quadrilateral.
7. Euclid of Alexandria
Euclid’s Data
Fifteen
definitions
magnitu
des
lo
ci
Ninety-five
statements
Conditions and
magnitudes
If two
magnitudes a
and b are
given, their
ratio is
given, and
that if one
magnitude is
given and
8. Euclid of Alexandria
E B D
CFA
We are told that if a given (rectangular) area AB is laid off
along a line segment of given length AC and if the area BC by
which the area AB falls short of the entire rectangle AD is
given, the dimensions of the rectangle BC are known.
9. Euclid of Alexandria
The elements
First
textbook
Introductory textbook
covering all elementary
mathematics
A bearing to the rest of
mathematics the same
sort of relation as that
which the letters of the
alphabet have in relation
to language.
10. Euclid of Alexandria
The elements
Thirteen
books
First half-
dozen
Elementary
Plane
Geometry
“The extremities of a line
are points”
“A straight line is a line in
which lies evenly with the
points on itself.”
“The extremities of a
surface are lines”
11. Postulat
es
1. To draw a straight line from any point to any point
2. To produce a finite straight line continuously in a
straight line.
3. To describe a circle with any center and radius.
4. That all angles are equal.
5. That, if a straight line falling on two straight line
makes the interior angles on the same side less
than two right angles, the two straight lines, if
produced indefinitely, meet on that side on which
the angles are less than the two right angles.
Euclid of Alexandria
12. Common
notions:
1. Things which are equal to the same thing are also
equal to one another.
2. If equals be added to equals, the wholes are equal.
3. If equals be subtracted from equals, the
remainders are equal.
4. Things which coincide with one another are equal
to one another.
5. The whole is greater than the part.
Euclid of Alexandria
DEATH OF ALEXANDER THE GREAT-led to internecine strife among the generals in the Greek army, but after 300 BCE, control of the Egyptian portion of the empire was firmly in the hands of thePTOLEMIES- Macedonian rulers of EgyptPTOLEMY I- laid the foundations for two institutions at Alexandria that would make it the leading center of scholarship for generations.MUSEUM and LIBRARY- both amply endowed by him and his sonPTOLEMY II-brought to this great research center men of outstanding scholarship in a variety of fields. And one of them is…EUCLID- author of the most successful mathematics textbook ever written entitledELEMENTS (Stoichia)- Perokahitnapakasikatnieuclid at kahit best-seller xa, remarkably little is known of his life.. He is so..OBSCURE- no birthplace associated with his name/Though samga edition saiyang books ginapadayagiyangpagkataongasiyadwsi Euclid of Megara, but this is a case of mistaken identityFrom the nature of his work, it is presumed that Euclid of Alexandria had studied with students of Plato,
Including some of his more important compositions such as TREATISE ON CONICS IN FOUR BOOKSTHE LOSS OF EUCLIDEAN PORISMS-particularly tantalizingtantalizing present participle of tan·ta·lize(Verb)VerbTorment or tease (someone) with the sight or promise of something unobtainable.Excite the senses or desires of (someone).PAPPUS-later reported that (NEXT)Others described porisms as a (NEXT)a (1) : something offered for consideration or acceptance :proposal (2) : a request for sexual intercourseb : the point to be discussed or maintained in argument usually stated in sentence form near the outsetc : a theorem or problem to be demonstrated or performed2a : an expression in language or signs of something that can be believed, doubted, or denied or is either true or falseb : the objective meaning of a proposition3: something of an indicated kind to be dealt with <the farm was never a paying proposition>
Five works of Euclid that have survived to our day: ELEMENTS, DATA,DIVISION OF FIGURES, PHAENOMENA AND OPTICSThe last mentioned is of interest to the ancients so they had divided the study of optical phenomena into three parts: OPTICS, CATOPTRICS nd DIOPTRICSNOTE:::!!!!!CATOPTRICA-in doubtful authenticity, being perhaps by Theon of Alexandria, who lived some six centuries later
EUCLID’S OPTICS-noteworthy for its espousal of an“EMISSION” THEORY OF VISION- according to which the eye sends out rays that travel to the object. Contrasted by the ARISTOTELIAN DOCTRINE-in which an activity in a medium travels in a straight line from the object to the eye.But it should be noted that the mathematics of perspective is the same, no matter which of the two theories is adopted.tanαtan 𝛽<𝛼𝛽 𝑖𝑓 0<𝛼<𝛽<𝜋2=one widely used in antiquity among the theorems found in Euclid’s OpticsEUCLID DIVISION OF FIGURES-work that would have been lost kung hindidahilsaArabic Scholars.hindiito nag survive nungtymsnggreekperobago pa nawala, may arabic translationna then later translated into latin then ultimately into current modern languagesEUCLID’S OPTICS-noteworthy for its espousal of an“EMISSION” THEORY OF VISION- according to which the eye sends out rays that travel to the object. Contrasted by the ARISTOTELIAN DOCTRINE-in which an activity in a medium travels in a straight line from the object to the eye.But it should be noted that the mathematics of perspective is the same, no matter which of the two theories is adopted.tanα/(tan 𝛽)<𝛼/𝛽 𝑖𝑓 0<𝛼<𝛽<𝜋/2=one widely used in antiquity among the theorems found in Euclid’s OpticsOne object of the Optics was to combat an Epicurean insistence that an object was just as large as it looked, with no allowance to be made for the foreshortening suggested by perspective.EUCLID DIVISION OF FIGURES-work that would have been lost kung hindidahilsaArabic Scholars.hindiito nag survive nungtymsnggreekperobago pa nawala, may arabic translationna then later translated into latin then ultimately into current modern languages
EUCLID’S DATA- somewhat similar in nature and purpose to the Division of Figures -a work that has come down to us through both the Greek and the Arabic. -composed for use at the Museum of Alexandria, serving as a companion volume to the first six books of the Elements in much way that a manual of tables supplements a textbook. -opens with FIFTEEN DEFINITIONS concerning MAGNITUDES AND LOCIThe body of the textcomprises NINETY-FIVE STATEMENTS concerning the implications of CONDITIONS AND MAGNITUDESThe first two state that ….LOCI-d set of all points whose location is determined by stated conditions
Some of the statements are geometric equivalents of the solution of quadratic equations. For example (NEXT)The shortcutThe geometric solution given by Euclid is equivalent to this, except that the negative sign before the radical is used.
(Surprise)a textbook that by no means the first oneElements of Euclid so far outdistanced competitors that it alone survivedELEMENTS was not, as sometimes thought, a compendium of all geometric knowledge instead (NEXT)ARITHMETIC-in the sense of the English “higher arithmetic” or the American “theory of numbers”SYNTHETIC GEOMETRY-of points, lines, planes, circles, and spheresProclus described the elements as (NEXT)Elements were intended as an exhaustive store of information ..daghankauang authors. Euclid himself made no claim of originality. Yes, the arrangements are his and He supplies the proofs but beyond that, it is difficult to estimate the degree of originalityBEARING-connection