Argument from abiogenesis

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For more information, see the TalkOrigins Archive article:
For more information, see the Wikipedia article:

The argument from abiogenesis concerns the origin of the earlies life forms from non-living matter, known as "abiogenesis". The exact process of abiogenesis is unknown and an ongoing area of research in the chemical sciences. Though many concepts about the beginning of life have been proposed and even demonstrated, and there is a rough framework for the overall stages of the process, as of yet, a standard model of abiogenesis has not been developed.


Creationists often claim that since abiogenesis could not naturally occur, it required the intervention of a designer.


Abiogenesis vs. evolution

For more information, see the TalkOrigins Archive article:


"Early on [evolution’s current view of]-abiogenesis was an integral part of evolution. [evolution’s current view of]-illusionists thought that 'spontaneous generation' of life would be found to occur everywhere on earth. That was shown to not be the case. [...] They now say that [evolution’s current view of]-abiogenesis is not part of evolution. [1]"

The historic relationship between scientific concepts is irrelevant and (ironically) commits the genetic fallacy. What matters is the current understanding of these concepts. In principle, God could could have created simple life and allowed evolutionary processes to take their course, or both both theories could be false, or both true. Attempting to link them, then disprove one to disprove the other is a non sequitur. A typical example of confusion between the two concepts is:

"Many who believe in evolution would tell you that billions of years ago, life began on the edge of an ancient tidal pool or deep in the ocean. [...] If the theory of evolution is true, it should offer a plausible explanation of how the first “simple” cell formed by chance. [...] To sidestep this dilemma, some evolutionary scientists would like to make a distinction between the theory of evolution and the question of the origin of life.[2]"

Yes, they are distinct theories. A theory does not need to describe all phenomena to be considered useful or valid. Apologists like to use the association fallacy to cast doubt on evolution.

Scientific background

Perhaps the simplest argument for abiogenesis is:

  1. The Earth formerly did not have life.
  2. More recently, life exists on earth.
  3. It is scientific to assume only natural processes occurred.
  4. Therefore, abiogenesis occurred (or possibly panspermia).








The Urey-Miller experiment

For more information, see the TalkOrigins Archive article:
For more information, see the Wikipedia article:





Later results


Researchers were able to reanalyze the residues from one of the original experiments, and found several amino acids that instruments in the 1950s were not sensitive enough to detect. [3] In other words, Miller and Urey were more successful than they realized.



Self replicating machines

For more information, see the Wikipedia article:

John von Neumann proposed a theoretical self-replicating machine which used surrounding resources to produce further copies of itself. Although different from living cells in many respects, it showed that a relatively simple logical system could propagate itself in an appropriate environment.


For more information, see the Wikipedia article:

Panspermia is a speculative theory that considers life on Earth to have originated elsewhere, developed and arrived on Earth from space. It is an alternate to the abiogenesis theory but still relies on natural processes. The obvious question it raises is where and how did like originate first? This is hard to resolve definitively in the short term because it may require seeking for life elsewhere in the universe. However, it is almost impossible to rule this possibility out, so the argument from abiogenesis will remain in doubt.

If abiogenesis occurred away from Earth and arrived by panspermia, we would not expect to see any evidence of abiogenesis on Earth.

Natural occurrence of many important chemicals

It is also clear that many substances that are needed for life occur naturally, even in space. [4]


Researchers have found that proteins have properties that may lend themselves to forming functionally useful shapes.

"This is how life, at least the biochemistry of life, could have gotten started [...] Evolution would have optimized the functions, but you don't need that to get started at a low level of efficiency. If you had a soup of our artificial proteins, even with no selection you could at least do low-level biochemistry. [5]"
"Given that such a limited number of binding pockets exist, proteins generated by combining amino acids at random will easily possess the full suite of binding pockets found throughout nature.[6]"

Arguments against abiogenesis

Personal incredulity

This argument amounts to "I known see how abiogenesis could have happened, so it didn't happen". It is an argument from ignorance.

Original replicator is too complex

For more information, see the TalkOrigins Archive article:

Life replicates itself in an either identical or nearly identical form, which distinguishes it from non-living matter. The first replicator, while simpler than modern life forms, was complex and unlikely to occur by chance or natural processes. Therefore, some intelligent intervention was required to get life going. [7]

"The supreme problem for Darwinists is explaining the origin of the first life. For unguided, naturalistic macroevolution to be true, the first life must have generated spontaneously from nonliving chemicals. Unfortunately for Darwinists, the first life-indeed any form of life-is by no means “simple.” [8]"

Leaving aside the issue that "Darwinists" address evolution, not abiogenesis, the apologist has no idea what the first life looked like. How can they claim that it was not simple or even that it was DNA based? This is an argument from ignorance.

Apologists like to compare the original replicator with an amoebae and argue that an amoebae's DNA could not occur by chance, but this is a false analogy because an amoebae is probably nothing like the original replicator. [9]

"Sagan was absolutely convinced that a simple string of prime numbers proves the existence of an intelligent being, but the equivalent of 1,000 encyclopedias in the first one-celled life does not.[8]"

The form that the first replicator might have taken and the environment in which it arose is unknown. However, it is almost certain that it was simpler and unlike the functioning of modern cells. It is therefore impossible to claim to any degree of certainty that it is unlikely to have arisen, because estimating the likelihood depends on unknown information. Since the argument fails to rule out other possibilities, it is an argument from ignorance.

"In summary, [...] the inability of modern science to develop a statistically probable mechanism is intriguing, this is not the place for a thoughtful person to wager his faith."

Francis Collins, The Language of God

Necessary cell ingredients cannot exist outside a cell

"The complex molecules in the simplest living thing cannot reproduce alone. Outside the cell, they break down. Inside the cell, they cannot reproduce without the help of other complex molecules.[2]"
"It turns out that DNA is inherently unstable, and the preservation of genetic information requires a complex symbiotic relationship between the cell and DNA that is so interdependent that neither could have arisen independently of the other.[10]"

While this may be true of modern cells, the first replicator was probably simpler and could use naturally occurring materials. DNA may not have been involved in abiogenesis at all.

No spontaneous generation of complex life

"Spontaneous generation of life has never been observed[8]"

Creationists often claim that Francesco Redi disproved abiogenesis in 1668 by showing that flies do not appear on meat if the meat is sealed from outside contamination. This idea often manifests in the so-called Peanut Butter argument against evolution. In fact, Redi disproved the theory of spontaneous generation, the idea that fully-formed modern flies spontaneously arise from meat.


The reason that the spontaneous generation of complex life has not been directly observed is that it probably takes millions of years, a wide variety of conditions and circumstances and a planet sized "test sample". Current models of abiogenesis do not claim life can emerge in short periods in small containers.

Of course, scientists have indirectly observed the formation of life in that at one time, the Earth did not exist and life (probably) existed no where else. Now, life exists. Therefore, life spontaneously arose.

Scientists claim they know exactly how abiogenesis occurred

"Many evolutionists as well as many creationists speak as if they know, beyond any doubt, how the first life came into existence.[8]"

No, scientists or evolutionists don't know yet and they don't claim they do. That is a straw man.

Scientists disagree

For more information, see the TalkOrigins Archive article:

Apologists claim that scientists disagree over how abiogenesis occurred.

"Other equally respected scientists who also support evolution disagree. [...] Why?[2]"

This demonstrates almost nothing. Almost all scientific theories have controversy surrounding them. Just because there is controversy, does not imply that they are all mistaken. By arguing that scientists are sometimes wrong, which is an obvious fact, is really a rhetorical technique for poisoning the well.

The argument is related to the teach the controversy movement.

Life always comes from life

For more information, see the TalkOrigins Archive article:
"Life always comes from preexisting life. However, if we go back far enough in time, is it really possible that this fundamental law was broken?[2]"

Making that statement without supporting is begging the question that abiogenesis didn't occur and an argument from incredulity.

No evidence

Quoting creationist scientists, apologists say:

"no empirical evidence supports the hypotheses of the spontaneous appearance of life on Earth from nothing but a molecular soup, and no significant advance in scientific knowledge leads in this direction[11]"

However, there is some evidence for abiogenesis. The most obvious evidence is that the early Earth was hostile to life and now it contains life.

Regarding the evidence for abiogenesis, we must remember that the event occurred billions of years ago. Also, it probably occurred at a molecular scale. For this reason, we might not expect much direct evidence of abiogenesis. Just because evidence of an event is not available does not make an event impossible. Science is continually progressing may way well discover direct evidence of abiogenesis. Since this argument would collapse completely in that eventually, it is a form of God of the gaps.

Analogy with human design

Apologists argue that life requires an intelligence to create it.

"If it takes an intelligent entity to create and program a lifeless robot, what would it take to create a living cell, let alone a human? [...] Keeping you out of the cell is a tough, flexible membrane that acts like a brick and mortar wall surrounding a factory.[2]"

This is a false analogy because the first replicator was probably existed on a molecular scale and was much simpler than a robot. Apologists put forward intelligent design as the explanation for life. However this is a poor analogy because cells operate quite differently from human designs.

"No human invention can compete with the technical brilliance evident in even the most basic of cells.[2]"

Human design is the primary example of intelligent design we have (although this risks the spotlight fallacy).

Scientists can only show intelligence creates life

"if scientists ever did construct a cell, they would accomplish something truly amazing—but would they prove that the cell could be made by accident? If anything, they would prove the very opposite, would they not? [...] whom or what does the scientist who performed the experiment represent? Does he or she represent blind chance or an intelligent entity?[2]"

This misses the point that scientists are trying to replicate the conditions that prevailed during the early Earth. Of course, scientists are involved with performing experiments but the experiments are intended to show that natural processes can produce the key ingredients of life. It is also unreasonable to expect scientists to create life in the lab by simulating natural processes because it most likely requires a vast time scale and a huge (planet sized) experiment.

Counter arguments

Simple systems can self replicate

In certain circumstances, very simple atoms and molecules can self replicate or exhibit structure, such as in crystals or snow flakes. Give that life probably began by a simple self replicating modules, this makes abiogenesis relatively more likely (although it is still hard to determine the probability of abiogenesis in absolute terms). [7]

Plenty of opportunity

Even if abiogenesis is only a slim possibility, it has plenty of opportunity for that to occur.

There are potentially millions of planets in the habitable zone of stars in our galaxy [12] and there are billions of galaxies. Only considering Earth when considering the likelihood of abiogenesis commits the Texas sharpshooter fallacy.

Experiments that attempt to replicate the conditions of the early Earth find that many important chemicals, such as amino acids, occur naturally without life. The oceans and surface of the Earth is large, providing many opportunities for abiogenesis. Also, planets exist for billions of years; the Earth is already 4.5 billion years old, which gives plenty of opportunities for abiogenesis.

Which God?

Main Article: Which God?

No specific God or religion is supported by the argument.


  1. [1]
  2. 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 The Origin of Life—Five Questions Worth Asking, 2010
  3. paper published in Science in 2008
  4. Rosetta’s comet contains ingredients for life
  5. [2]
  6. [3]
  7. 7.0 7.1 [4]
  8. 8.0 8.1 8.2 8.3 I Don't Have Enough Faith to be an Atheist
  9. [5]
  10. [6]
  11. Alexandre Meinesz
  12. [7]

See also

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