Euclid Elements, 9.prop.20
Christopher Blackwell / Euclid
- Created on 2018-03-29 14:12:14
- Translated by Heath
- Aligned by Christopher Blackwell
Euclid 9.20. The "infinitude of primes".
Ἑλληνική Transliterate
English
urn:cts:greekLit:tlg1799.tlg001.heiberg:9.prop.20
urn:cts:greekLit:tlg1799.tlg001.heath:9.prop.20
Οἱ πρῶτοι ἀριθμοὶ πλείους εἰσὶ παντὸς τοῦ προτεθέντος πλήθους πρώτων ἀριθμῶν .
Ἔστωσαν οἱ προτεθέντες πρῶτοι ἀριθμοὶ οἱ Α , Β , Γ : λέγω , ὅτι τῶν Α , Β , Γ πλείους εἰσὶ πρῶτοι ἀριθμοί .
Εἰλήφθω γὰρ ὁ ὑπὸ τῶν Α , Β , Γ ἐλάχιστος μετρούμενος καὶ ἔστω ὁ ΔΕ , καὶ προσκείσθω τῷ ΔΕ μονὰς ἡ ΔΖ .
ὁ δὴ ΕΖ ἤτοι πρῶτός ἐστιν ἢ οὔ .
ἔστω πρότερον πρῶτος : εὑρημένοι ἄρα εἰσὶ πρῶτοι ἀριθμοὶ οἱ Α , Β , Γ , ΕΖ πλείους τῶν Α , Β , Γ .
Ἀλλὰ δὴ μὴ ἔστω ὁ ΕΖ πρῶτος : ὑπὸ πρώτου ἄρα τινὸς ἀριθμοῦ μετρεῖται .
μετρείσθω ὑπὸ πρώτου τοῦ Η :
λέγω , ὅτι ὁ Η οὐδενὶ τῶν Α , Β , Γ ἐστιν ὁ αὐτός .
εἰ γὰρ δυνατόν , ἔστω .
οἱ δὲ Α , Β , Γ τὸν ΔΕ μετροῦσιν :
καὶ ὁ Η ἄρα τὸν ΔΕ μετρήσει .
μετρεῖ δὲ καὶ τὸν ΕΖ :
καὶ λοιπὴν τὴν ΔΖ μονάδα μετρήσει ὁ Η ἀριθμὸς ὤν : ὅπερ ἄτοπον .
οὐκ ἄρα ὁ Η ἑνὶ τῶν Α , Β , Γ ἐστιν ὁ αὐτός .
καὶ ὑπόκειται πρῶτος .
εὑρημένοι ἄρα εἰσὶ πρῶτοι ἀριθμοὶ πλείους τοῦ προτεθέντος πλήθους τῶν Α , Β , Γ οἱ Α , Β , Γ , Η :
ὅπερ ἔδει δεῖξαι .
Ἔστωσαν οἱ προτεθέντες πρῶτοι ἀριθμοὶ οἱ Α , Β , Γ : λέγω , ὅτι τῶν Α , Β , Γ πλείους εἰσὶ πρῶτοι ἀριθμοί .
Εἰλήφθω γὰρ ὁ ὑπὸ τῶν Α , Β , Γ ἐλάχιστος μετρούμενος καὶ ἔστω ὁ ΔΕ , καὶ προσκείσθω τῷ ΔΕ μονὰς ἡ ΔΖ .
ὁ δὴ ΕΖ ἤτοι πρῶτός ἐστιν ἢ οὔ .
ἔστω πρότερον πρῶτος : εὑρημένοι ἄρα εἰσὶ πρῶτοι ἀριθμοὶ οἱ Α , Β , Γ , ΕΖ πλείους τῶν Α , Β , Γ .
Ἀλλὰ δὴ μὴ ἔστω ὁ ΕΖ πρῶτος : ὑπὸ πρώτου ἄρα τινὸς ἀριθμοῦ μετρεῖται .
μετρείσθω ὑπὸ πρώτου τοῦ Η :
λέγω , ὅτι ὁ Η οὐδενὶ τῶν Α , Β , Γ ἐστιν ὁ αὐτός .
εἰ γὰρ δυνατόν , ἔστω .
οἱ δὲ Α , Β , Γ τὸν ΔΕ μετροῦσιν :
καὶ ὁ Η ἄρα τὸν ΔΕ μετρήσει .
μετρεῖ δὲ καὶ τὸν ΕΖ :
καὶ λοιπὴν τὴν ΔΖ μονάδα μετρήσει ὁ Η ἀριθμὸς ὤν : ὅπερ ἄτοπον .
οὐκ ἄρα ὁ Η ἑνὶ τῶν Α , Β , Γ ἐστιν ὁ αὐτός .
καὶ ὑπόκειται πρῶτος .
εὑρημένοι ἄρα εἰσὶ πρῶτοι ἀριθμοὶ πλείους τοῦ προτεθέντος πλήθους τῶν Α , Β , Γ οἱ Α , Β , Γ , Η :
ὅπερ ἔδει δεῖξαι .
Prime
numbers
are
more
than
any
assigned
multitude
of
prime
numbers
.
Let A , B , C be the assigned prime numbers ; I say that there are more prime numbers than A , B , C .
For let the least number measured by A , B , C be taken , and let it be DE ; let the unit DF be added to DE .
Then EF is either prime or not .
First , let it be prime ; then the prime numbers A , B , C , EF have been found which are more than A , B , C .
Next , let EF not be prime ; therefore it is measured by some prime number .
Let it be measured by the prime number G .
I say that G is not the same with any of the numbers A , B , C .
For , if possible , let it be so .
Now A , B , C measure DE ; therefore G also will measure DE .
But it also measures EF .
Therefore G , being a number , will measure the remainder , the unit DF : which is absurd .
Therefore G is not the same with any one of the numbers A , B , C .
And by hypothesis it is prime .
Therefore the prime numbers A , B , C , G have been found which are more than the assigned multitude of A , B , C .
Q . E . D .
Let A , B , C be the assigned prime numbers ; I say that there are more prime numbers than A , B , C .
For let the least number measured by A , B , C be taken , and let it be DE ; let the unit DF be added to DE .
Then EF is either prime or not .
First , let it be prime ; then the prime numbers A , B , C , EF have been found which are more than A , B , C .
Next , let EF not be prime ; therefore it is measured by some prime number .
Let it be measured by the prime number G .
I say that G is not the same with any of the numbers A , B , C .
For , if possible , let it be so .
Now A , B , C measure DE ; therefore G also will measure DE .
But it also measures EF .
Therefore G , being a number , will measure the remainder , the unit DF : which is absurd .
Therefore G is not the same with any one of the numbers A , B , C .
And by hypothesis it is prime .
Therefore the prime numbers A , B , C , G have been found which are more than the assigned multitude of A , B , C .
Q . E . D .