The Fish in the Bathtub

One weekend I got into a discussion with a very talented physical chemist, a former colleague, on the topic of God, the Bible and evolution. I kept noticing that his comments with respect to evolution were inconsistent with basic concepts the two of us would deal with routinely in chemistry.

I thought I could focus the issues more clearly by asking him: If he were to fill his bathtub with water and come back in a million years, would he expect to find a fish swimming there?

Naturally, I expected the answer to be “no”, since we know that water molecules don’t get converted into organic molecules, and so on. I was hoping to systematically go through with him what kind of assumptions would be necessary for that fish to be produced under “natural” and unguided conditions.

He told me confidently that, no, he would not find a fish there, even after a million years. I was getting my second question ready, about a fish in a swimming pool out in the sunlight, when he then added, “but in a billion years there might be a fish there”.

His answer was adamant: “With enough time everything is possible.”

I couldn’t believe my ears. As I pressed him about the things required, such as the formation of optically active biomolecules, information encoding and decoding and DNA, male/female reproduction, and so on,1 his answer was adamant: “With enough time everything is possible.”

I pointed out the obvious flaw in this reasoning. After a short period of time, the water in this bathtub has reached thermal equilibrium. Any other molecules dissolved in the water quickly arrive at a random steady state, and there is no difference in the distribution after a thousand years–far less if everything has been sitting there for a billion years. In fact, I claimed, if any abnormal structures or organization were to result by the strangest coincidence, the chances were better during the initial turbulence of water gushing out of the tap. The chances of structures far from thermodynamic equilibrium (as are all life forms) arising by chance can only decrease with time.

This magical claim that “given enough time anything is possible”, that even the most complex organisms could arise by chance if we were to wait long enough, is not what an engineer or physical scientist observes in the real world. Here are some examples:

1. In a closed room at a constant temperature, it is statistically possible that all the oxygen molecules could accumulate, by sheer chance, up in one corner long enough for everyone to suffocate. Shall we argue that if we wait long enough in a room, we will eventually observe this? Actually, no. Gas molecules bump into each other randomly, and continue moving until the next collision. Because they travel, on average, longest in a straight line in the direction where there are the fewest molecules, they thus spread themselves out ever more evenly with time until a steady state is reached.
   
   In fact, if the individual gases which together make up air had been pumped into the room, the chances of observing all the oxygen clumped in one corner are better within a short period of time, but the probability will steadily decrease as random effects lead to the most probable state, which is the most “randomized” or disordered one.
2. Most footballs are not perfectly airtight. After some time they will have lost some pressure. It is not sensible to argue that with time anything is possible, that eventually the ball will start to reinflate itself. Even though any individual air molecule could, by chance, enter the ball from without, the probability of collisions within the ball is much greater than the collisions per unit area outside the ball. So the overwhelming probability is that more molecules will leak out than in. Thus, the more time that passes, the more certain it is that the ball will deflate, not spontaneously reinflate.
3. A cherry seed can sprout and create a tree able to produce many such seeds. Could such a seed arise by waiting long enough? A collection of chemicals lacking a protective shell and the internal machinery and programmed information to grow has a decreasing chance of producing a functional seed as time goes on: the component chemicals will decompose, or be washed away by rain, or disintegrate in ultraviolet light.

On this basis it seems amazing that atheists would expect to find life on other planets. Life is decidedly not a natural phenomenon which automatically results “given the right conditions”. What if life was discovered on other planets, and it could be shown that this was not life which had originated from Earth somehow?2 Even though this would seem exceedingly strange from a Biblical viewpoint, to me it would be further proof, if not absolute proof, of a Creator. Something as incredibly, hopelessly complex as living forms requires the most fantastic leaps of imagination to think it could appear by chance just once; to contemplate it happening by chance twice should be regarded as beyond rational discussion.3

Furthermore, the ecosystems needed to support life (as we now see them in this post-Fall world) are incredibly complex and finely balanced. It is not only unreasonable to believe that they could arise by chance, but also totally unreasonable to think that they could survive for millions of years. The longer the time period, the greater the chance of something going amiss, such as: an unstoppable disease spreading; a killer meteor hitting the Earth; massive climate changes; bad mutations accumulating; major imbalances in food supply or nutrient ratios. The possibilities are almost endless about what could go wrong, given the high degree of interdependence of the systems in the living world.

The claim that, with time, anything is possible, including the creation and perpetuation of life, is not based on any scientific principle. Rather, the opposite is true: complex and improbable structures of any kind tend to disintegrate over time.