Complexity Can Be Specified
Industry pays computer programmers more than it pays secretaries, though in a sense they both do the same thing. A programmer may write equations into a program that a physicist can use to design a lens. A secretary may type a report on a word processor. Both are really programming a computer. The secretary programs the computer to produce the report by typing one letter at a time. The programmer writes a few lines of equations that may produce as much output as the report, or more. Which one is doing the more complex task? The secretary’s product is more complex because it takes more detailed instructions to specify exactly what the computer is to do. The length of the programmer’s program may only be a few kilobytes, but the secretary’s report is about 6 kilobytes per page.
Industry personnel officers may justify paying computer programmers more than secretaries because the amount of training the programmers require takes somewhat longer than the training for secretaries, and also because more people are ready to be secretaries than programmers. Apart from any lamentable inequities in remuneration practices, the point of the example above is to show that we can measure complexity in terms of the number of small instructions it takes to produce the product.
Big software packages may run to many megabytes, but most of such packages these days are parts of the graphical user interface, the pictures people need to use the programs. A crystal is not very complex because, after describing one cell, we only need to give the number of cells in each of three directions. A photograph is much more complex than a mathematical program or a page of text. We can’t send a picture of ourselves in a line of equations.
The foregoing enables us to appreciate the complexity of DNA, the molecule that specifies the genetic information in all living organisms. We should think of DNA as a ladder twisted into a spiral, something like a spiral staircase. Each rung of the ladder consists of two molecules that fit neatly together. There are two pairs of molecules that make rungs that are almost alike, and the two kinds of rungs are symmetrical, that is, they can fit into the ladder with either end to one side. If we choose one side of the ladder to study, there are four possible molecules at each place where is a rung is connected. The other side of the ladder is complementary. Whatever sequence of molecules appears on one side has the same sequence of opposite rung ends on the other side.
Enzymes work with groups of three rungs. In a group of three rung ends, each end can be any of four molecules, so there are 4x4x4=64 possible combinations in any group of three. Enzymes use these combinations to specify 21 different nucleic acids. That is, there may be two or three different combinations of “rung ends” or molecules that specify the same nucleic acid. Other combinations have other uses. There is a start code that tells an enzyme where to start reproducing the side, and a stop code that tells the enzyme when it has read all the specifications for a given protein.
People have 46 long strings of DNA code wound up as chromosomes in the nuclei of their cells. Of these, they inherit 23 from their mother and 23 from their father. Each set of 23 chromosomes is the complete specification for a human being. The information is about the size of a 23-volume encyclopedia. In some way (as yet unknown) the enzymes choose which of the two encyclopedias to read when expressing the different characteristics in the cells of our bodies.
The richly varied forms of all living species are specified in DNA code. A measure of their complexity is the amount of information in the code. The code specifies the complexity of the species.
We can now appreciate why random action cannot build up the simple very far into the complex. The complexity of the genome of the tiniest living organism is far greater than the complexity of organic compounds, and these in turn are much more complex than the 92 elements.
Industry personnel officers may justify paying computer programmers more than secretaries because the amount of training the programmers require takes somewhat longer than the training for secretaries, and also because more people are ready to be secretaries than programmers. Apart from any lamentable inequities in remuneration practices, the point of the example above is to show that we can measure complexity in terms of the number of small instructions it takes to produce the product.
Big software packages may run to many megabytes, but most of such packages these days are parts of the graphical user interface, the pictures people need to use the programs. A crystal is not very complex because, after describing one cell, we only need to give the number of cells in each of three directions. A photograph is much more complex than a mathematical program or a page of text. We can’t send a picture of ourselves in a line of equations.
The foregoing enables us to appreciate the complexity of DNA, the molecule that specifies the genetic information in all living organisms. We should think of DNA as a ladder twisted into a spiral, something like a spiral staircase. Each rung of the ladder consists of two molecules that fit neatly together. There are two pairs of molecules that make rungs that are almost alike, and the two kinds of rungs are symmetrical, that is, they can fit into the ladder with either end to one side. If we choose one side of the ladder to study, there are four possible molecules at each place where is a rung is connected. The other side of the ladder is complementary. Whatever sequence of molecules appears on one side has the same sequence of opposite rung ends on the other side.
Enzymes work with groups of three rungs. In a group of three rung ends, each end can be any of four molecules, so there are 4x4x4=64 possible combinations in any group of three. Enzymes use these combinations to specify 21 different nucleic acids. That is, there may be two or three different combinations of “rung ends” or molecules that specify the same nucleic acid. Other combinations have other uses. There is a start code that tells an enzyme where to start reproducing the side, and a stop code that tells the enzyme when it has read all the specifications for a given protein.
People have 46 long strings of DNA code wound up as chromosomes in the nuclei of their cells. Of these, they inherit 23 from their mother and 23 from their father. Each set of 23 chromosomes is the complete specification for a human being. The information is about the size of a 23-volume encyclopedia. In some way (as yet unknown) the enzymes choose which of the two encyclopedias to read when expressing the different characteristics in the cells of our bodies.
The richly varied forms of all living species are specified in DNA code. A measure of their complexity is the amount of information in the code. The code specifies the complexity of the species.
We can now appreciate why random action cannot build up the simple very far into the complex. The complexity of the genome of the tiniest living organism is far greater than the complexity of organic compounds, and these in turn are much more complex than the 92 elements.
