HAVE you ever cut your finger? Of course you have. Everybody does, many times in a lifetime. Yet you have survived these accidents or you would not be reading these words. Have you ever considered what would have happened if your cut finger had not stopped bleeding? Inevitably, you would have died. Your blood pressure would have dropped slowly down until your heart stopped beating. Cuts and grazes can be survived only because the body has a built-in repair system, standing by like paramedics at a sports fixture, ready to cope with the emergency.

We take this remarkable mechanism for granted. We cut our finger, and unless we are unfortunate enough to be a haemophiliac, we put on a bandage and forget about it. But when you ask how this body defence system came into existence in the first place, the argument for Creation becomes overwhelming. Put the other way round, simple logic rules out natural selection as a satisfactory explanation.

Let us review, for a moment, what happens when we cut ourselves. Suppose you cut yourself accidentally. Quickly, you apply your handkerchief. Within a minute or two the bright red beads of liquid begin to dry up and turn dark.By next morninga protective scab will cover the wound, and a week later all that is left is a faint scar. What actually happens during those first vital minutes?

Blood is the transport system of the body. It carries oxygen and sugar for the muscles, hormones for growth and reproduction, and waste products on their way to be removed—truly, as the Law of Moses says, “life is in the blood”.

The human body has around five litres (9 pints) of blood, pumped round under pressure by the heart like the cooling pump that sends water from the radiator to the engine of a car.

Because the blood is under pressure, it leaks rapidly if the skin is punctured, especially if many of the tiny tubes or capillaries are severed in quantity. When a car radiator springs a leak, the water does not stop running. In a short time it will empty all its contents on to the road, and the car will grind to a halt with the engine seized. But human blood is different. It automatically starts to plug the hole in the skin as soon as it begins to leak out, sealing the wound with a mat of tough fibres that bind together and form a plug.

What makes blood clot? The fibrous mat comes from a protein in the blood called fibrinogen. Normally fibrinogen is liquid, but when it is activated by the presence of another agent, thrombin, the fibrinogen forms strings, called fibrin. Thrombin itself has to be switched from an inactive form called prothrombin before it can do its work. When the skin and the tiny blood vessels are torn, fragments of bone marrow cells called platelets accumulate at the damaged ends, and their presence starts the complicated unlocking process of converting prothrombin to thrombin, and fibrinogen to fibrin, in that order.


Why do we need such a complicated multistage process to start off a blood clot? The answer is simple. If the blood were to clot accidentally inside the body, a lump of fibrin would soon clog up a major distribution pipe or artery, and we would die from gangrene or a stroke. The multistage unlocking procedure is a vital safety device.

It is just like drawing money from a cash machine at a bank. It would not do to have one simple number as the code. It would be too easy for a stranger to guess the number and walk away with money from your account. The machine insists that two codes are present together, both exactly correct. One of these is the invisible magnetic number on your cash card, and the other your unique PIN number that you have to enter from memory before the machine will produce the cash. So it is with blood clotting; only when prothrombin has turned to thrombin can fibrinogen go ahead and make the clot.

Now the point is how could a complex mechanism like this develop? It is mind-boggling that a remarkable protein should arise spontaneously in the blood which is capable of forming fibres fast enough and strong enough to close off a hole in the skin. Years of automobile engineering have failed to produce a reliable radiator coolant that will automatically seal a leak without forming sludge in other parts of the engine. To imagine a second, separate interlock mechanism also arising spontaneously in the blood stretches imagination to the limit.

As we have seen, every human being experiences cuts and grazes. The same is true for other animals. The very first creature with a blood system would have needed the blood sealing mechanism for survival. If it lacked fibrinogen, the animal would bleed to death as soon as its skin was damaged. And it would leave no descendants. There is no room for evolution to manoeuvre. Even if we assume that after thousands of false starts a primitive blood sealing mechanism did arise allowing a perilous form of life to continue, how did the separate mechanism develop to stop blood clotting unnecessarily?

There could not be a gradual elaboration of prothrombin and its activator enzyme. Its effect has to be all or nothing. Either you have a locking mechanism, or you don’t. There can be no halfway stage. If fibrinogen only partly turns to fibrin, you bleed to death. There would have to be a set point, one particular generation in which fibrinogen refused to change to fibrin unless thrombin was present. It sounds pretty unlikely.

In the end, you arrive at a position where you say to yourself—it is easier to believe in an intelligent Designer who, foreseeing the vulnerability of animal skin, built into the blood a sealant mechanism, and an anti-coagulant safety lock.

The Bible tells us that God, who loves His Creation, treats life as a very precious thing: and “the life of the flesh is in the blood” (Leviticus 17:11). He therefore told His people not to eat it; they were also to think of it as being a precious thing. This is because the lifeblood of God’s Son was poured out on the cross of Calvary, and it brings Jesus’ followers the hope of eternal life, free from the peril of accident, disease and death.