(continued from last post...)
Even numbers are divided into three classes: evenly-even, evenly-odd, and oddly-odd.
The evenly-odd numbers are all in duple ration from unity; thus 1,2 4, 8, 16, 32, 64, 128, 256, 512, and 1024. The proof of the perfect evenly-even number is that it can be halved and the halves again halved back to unity, as half of 64 = 32; half of 32 = 16; half of 16 = 8; half of 8 = 4; half of 4 = 2; half of 2 = 1; beyond unity it is impossible to go.
The evenly-even numbers posses certain unique properties. The sum of any number of terms but the last term is always equal to the last term minus one. For example: the sun of the first and second terms (1+2) equals the third term (4) minus one; or, the sum of the first, second, third, and fourth terms (1+2+3+4+8) equals the fifth term (16) minus one.
In a series of evenly-even numbers, the first mulitiplied by the last equals the last; te second multiplied by the second from the last equals the last, and so on until in an odd series one number remains, which multiplied by itself equals the last number of the series; or, in an even series two numbers remain, which multiplied by each other give the last number of the series. For example, 1, 2, 4, 8, 16 is an odd series. The first number (1) multiplied by the last number (16) equals the last number (16). The second number (2) multiplied by the second from the last number (8) equals the last number (16). Being an odd series, the 4 is left in the center, and this multiplied by itself also equals the last number (16).
The evenly-odd numbers are those which, when halved, are incapable of further division by halving. They are formed by taking the odd numbers in sequential order and multiplying them by 2. By this process the odd numbers 1, 3, 5, 7, 9, 11 produce the evenly-odd numbers 2, 6, 10, 14, 18, 22. Thus, every once, as 2, which becomes two 1's and cannot be divided further; or 6, which becomes two 3's and cannot be divided further.
The evenly-odd numbers are also remarkable in that each term is one-half of the sum of the terms on either side of it. For example: 10 is one-half of the sum of 6 and 14; 18 is one-half the sum of 14 and 22; and 6 is one-half the sum of 2 and 10.
Even numbers are also divided into another three classes: superperfect, deficient, and perfect.
Superperfect or superabundant numbers are such as have the sum of their fractional parts greater than themselves. For example: half of 24 = 12; one fourth = 6; one third = 8; one sixth = 4; one twelveth = 2; and one twenty-fourth = 1. The sum of these parts (12+6+8+4+2+1) is 33, which is in excess of 24, the original number.
Deficient numbers are such as have the sum of their fractional parts less than themselves. For example: half of 14 = 7; one-seventh = 2; and one-fourteenth = 1. The sum of these parts (7+2+1) is 10, which is less than 14, the original number.
Perfect numbers are such as have the sum of their fractional parts equal to themselves. For example: half of 28 = 14; one-fourth = 7; one-seventh = 4; one-fourteenth = 2; and one-twenty-eighth = 1. The sum of these parts (14+7+4+2+1) is equal to 28.
The perfect numbers are extremely rare. There is only one between 1 and 10, namely 6; one between 10 and 100, namely 28; one between 100 and 1000, namely 496; and one between 1000 and 10000, namely 8128.
Perfect numbers when multiplied by 2 produce superabundant numbers, and when divided by 2 produce deficient numbers.
The Pythagoreans evolved their philosophy from the science of numbers. The following quotation from Theoretic Arithmetic is an excellent example of this practice:
"Perfect numbers, therefore, are beautiful images of the virtues which are certain media between excess and defect, and are not summits, as by some of the ancients they were supposed to be. And evil indeed is opposed to evil, but both are opposed to one good. Good, however, is never opposed to good, but to two evils at one and the same time. Thus timidity is opposed to audacity, to both [of] which the want of true courage is common; but both timidity and audacity are opposed to fortitude. Craft also is opposed to fatuity, to both [of] which the want of intellect is common; and both these are opposed to prudence. Thus, too, profusion is opposed to avarice, to both [of] which illiberality is common; and both these are opposed to liberality. And in a similar manner in the other virtues; by all [of] which it is evident that perfect numbers have a great similutude to the virtues. But they also resemble the virtues on another account; for they are rarely found, as being few, and they are generated in a very constant order. On the contrary, an infinite multitude of superabundant and diminished numbers may be found, nor are they disposed in any orderly series, nor generated from any certain end; and hence they have a great similitude to the vices, which are numerous, inordinate, and indefinite."
Even numbers are divided into three classes: evenly-even, evenly-odd, and oddly-odd.
The evenly-odd numbers are all in duple ration from unity; thus 1,2 4, 8, 16, 32, 64, 128, 256, 512, and 1024. The proof of the perfect evenly-even number is that it can be halved and the halves again halved back to unity, as half of 64 = 32; half of 32 = 16; half of 16 = 8; half of 8 = 4; half of 4 = 2; half of 2 = 1; beyond unity it is impossible to go.
The evenly-even numbers posses certain unique properties. The sum of any number of terms but the last term is always equal to the last term minus one. For example: the sun of the first and second terms (1+2) equals the third term (4) minus one; or, the sum of the first, second, third, and fourth terms (1+2+3+4+8) equals the fifth term (16) minus one.
In a series of evenly-even numbers, the first mulitiplied by the last equals the last; te second multiplied by the second from the last equals the last, and so on until in an odd series one number remains, which multiplied by itself equals the last number of the series; or, in an even series two numbers remain, which multiplied by each other give the last number of the series. For example, 1, 2, 4, 8, 16 is an odd series. The first number (1) multiplied by the last number (16) equals the last number (16). The second number (2) multiplied by the second from the last number (8) equals the last number (16). Being an odd series, the 4 is left in the center, and this multiplied by itself also equals the last number (16).
The evenly-odd numbers are those which, when halved, are incapable of further division by halving. They are formed by taking the odd numbers in sequential order and multiplying them by 2. By this process the odd numbers 1, 3, 5, 7, 9, 11 produce the evenly-odd numbers 2, 6, 10, 14, 18, 22. Thus, every once, as 2, which becomes two 1's and cannot be divided further; or 6, which becomes two 3's and cannot be divided further.
The evenly-odd numbers are also remarkable in that each term is one-half of the sum of the terms on either side of it. For example: 10 is one-half of the sum of 6 and 14; 18 is one-half the sum of 14 and 22; and 6 is one-half the sum of 2 and 10.
Even numbers are also divided into another three classes: superperfect, deficient, and perfect.
Superperfect or superabundant numbers are such as have the sum of their fractional parts greater than themselves. For example: half of 24 = 12; one fourth = 6; one third = 8; one sixth = 4; one twelveth = 2; and one twenty-fourth = 1. The sum of these parts (12+6+8+4+2+1) is 33, which is in excess of 24, the original number.
Deficient numbers are such as have the sum of their fractional parts less than themselves. For example: half of 14 = 7; one-seventh = 2; and one-fourteenth = 1. The sum of these parts (7+2+1) is 10, which is less than 14, the original number.
Perfect numbers are such as have the sum of their fractional parts equal to themselves. For example: half of 28 = 14; one-fourth = 7; one-seventh = 4; one-fourteenth = 2; and one-twenty-eighth = 1. The sum of these parts (14+7+4+2+1) is equal to 28.
The perfect numbers are extremely rare. There is only one between 1 and 10, namely 6; one between 10 and 100, namely 28; one between 100 and 1000, namely 496; and one between 1000 and 10000, namely 8128.
Perfect numbers when multiplied by 2 produce superabundant numbers, and when divided by 2 produce deficient numbers.
The Pythagoreans evolved their philosophy from the science of numbers. The following quotation from Theoretic Arithmetic is an excellent example of this practice:
"Perfect numbers, therefore, are beautiful images of the virtues which are certain media between excess and defect, and are not summits, as by some of the ancients they were supposed to be. And evil indeed is opposed to evil, but both are opposed to one good. Good, however, is never opposed to good, but to two evils at one and the same time. Thus timidity is opposed to audacity, to both [of] which the want of true courage is common; but both timidity and audacity are opposed to fortitude. Craft also is opposed to fatuity, to both [of] which the want of intellect is common; and both these are opposed to prudence. Thus, too, profusion is opposed to avarice, to both [of] which illiberality is common; and both these are opposed to liberality. And in a similar manner in the other virtues; by all [of] which it is evident that perfect numbers have a great similutude to the virtues. But they also resemble the virtues on another account; for they are rarely found, as being few, and they are generated in a very constant order. On the contrary, an infinite multitude of superabundant and diminished numbers may be found, nor are they disposed in any orderly series, nor generated from any certain end; and hence they have a great similitude to the vices, which are numerous, inordinate, and indefinite."