Argument from potential

Argument from potential refers to the philosophical stance that the moral worth of X is derived from and tied to its potential.
While 'potential' can be part of a sound argument, it is often used inconsistently and/or in a fallacious way.

Definition

Potential is used in different, but ultimately related, ways.

As an expression of ignorance

"Potentially", like "maybe" or "possibly" can be used in a way that is not intended to assert that a thing is known to actually be possible, but rather that it is unknown to us if the thing is possible or not, and thus "maybe" it is possible in so far as our knowledge provides but could in fact be impossible without us knowing this.

This use is most relevant to the precautionary/cautionary principle.

For example, in a hypothetical world where animal moral value was not well established in science and philosophy, to arrive at veganism from the precautionary principle we would need only admit that we *don't know* if animals have moral value or not (that they are potentially of moral value in the sense of the unknown, e.g. if there were still scientific questions of sentience, or philosophical questions) and that we *don't know* if it's wrong to eat them if they do, because veganism follows from the precautionary principle if they even may have moral value and if it even may be wrong to eat them given it's practicable to avoid it (as the scientific questions on nutrition and food production *are* settled).

To give an analogous example: You are driving and see a bassinet in the road. You don't know if this bassinet contains a baby or not, you may speculate on the probability, but you can not see inside. Ought you swerve slightly to avoid running over it on the off chance it contains a baby? The cautionary principle would say you should.

As an assertion of possibility

"Potentially" can also mean an assertion of actual possibility, in that we know scientifically that something certainly is possible given some conditions or random outcomes.

Random outcome

This is probably the most uncomplicated sense of the meaning, because it doesn't rely on human intervention and open a can of worms with respect to free will and causality. For example, it is possible for a radioisotope to decay, and there's a certain chance of decay over time as stipulated by the isotope's half-life. A single atom of uranium has the potential to decay tomorrow despite its 4.5 billion year half-life. The odds are very very low, but the potential is still there, and is pretty much outside the control of humans (though humans can decrease the chance of decay by accelerating the atom resulting in time dilation, we can not eliminate it entirely). Even for a non-radioactive atom, there is potential to change into something else due to chance collision with some kind of high energy particle outside our control -- at astronomically small odds.

Given certain conditions

This sense of potential is more philosophically complicated, because it relies on something we can better control (though not perfectly). For instance, we might say a seed has the potential to become a tree -- but only if we plant it and give it water, sunlight, and the nutrients it needs. It does not have the potential to become a tree if it's not in the right environment, such as if being digested.

A viable seed on your plate has a potential to become a tree proportionate to its chance of being planted, and less than the inversely proportional to the probability of your chewing it up eating it. Here potentiality is a sliding scale, and it becomes entangled with human decisions and concepts of free will. This makes it a very messy concept to involve in moral valuation.

Biologically, a fetus (or even a single skin cell) has the potential to become a fully functioning human being, but only if given the right nutrients and care to reach that point (and for the cell, part of that is the right chemical signals to revert to a stem cell and then differentiate to become a fetal clone). If left to its own devices in the vacuum of space these have no potential. If the fetus is to be aborted, likewise, it has no potential. If the skin cell is left on the ground to desiccate and decompose, likewise, the potential is lost if the DNA is lost.

This is very salient to certain abortion questions in philosophy, because if the conditions are undefined assertions of fetal value based on potential are not meaningful, and if the conditions are unlimited then errant skin cells gain moral value on the same basis.

As an assertion of plausibility

The sense of potential that refers to plausibility builds upon assertions of possibility -- it must first be possible to be plausible. The difference here is that there is an arbitrary threshold at which the likelihood is high enough to say it has potential, under which it is said to have none.

The chances, for instance, of a skin cell being put in an environment where it will differentiate into a fetus and then be incubated to the point of viability are often lower than the chances of a pregnancy being carried to term (even by a woman who had intended to abort). There are two problems with probability thresholds:

1. They are arbitrary. This doesn't reflect well on what would be assumed to be an objective claim.

2. The probability of no potential increases to 100% as an intervention proceeds. E.g. for a woman considering an abortion the fetus may have a 50% chance, a woman decided it may have a 5% chance, a woman decided who has an appointment it may have a 1% chance, for a woman who then shows up to the appointment and is in the procedure room it may have a 0.0001% chance. Because the moment the act is done, for example of abortion, coincides with the moment the subject under consideration (such as the fetus) loses all potential to reach the necessary state, the ultimate act that terminates that potential can never be immoral based on potential itself granting moral value to a subject.

Neither of these issues appears easily surmountable, however, potential can be seen as a spectrum instead of a binary assertion.

As a degree of probability

Potential is coherent and non-arbitrary when speaking of degree, but in an astronomical sense everything that is possible (even if it would be unlikely to happen in the lifetime of the universe) is on that spectrum. Thus, having *some* potential is not adequate to dictate moral value in a deontological sense -- otherwise it leaves open endless possibilities when it comes to moral worth, that have to be considered for any existing being or object, since everything has the potential for anything. For instance, a rock waking up and becoming sentient due to the highly improbable arrangement via diffusion and even tunneling of the silicon atoms and dopants inside into a natural computer brain and forming solar cells on its surface to power it. You might never see it in a googleplex to the googleplex lifetimes of the universe, but based on the laws of physics it remains possible and the probability could be computed.

Threshold for value fail for the same reason explained above regarding assertions of plausibility. As such, if potential is related to moral value, it must be the potential itself that is valued (in a consequentialist sense) rather than acts against agents given value by their potential. In other words, acts that lower potential would be wrong but acts that raise potential would be right.

As an expression of supernatural free will

A more esoteric use of "potential" can refer more specifically to a supernatural concept of free will, by which a soul makes a free and non-random choice not dictated by nature or environmental determinism. In this case, the claim that humans have a certain potential but non-humans do not is just a deceptive substitution for the claim that humans have souls and non-human animals do not -- thus serving only as a distraction from the actual conversation which is a question of supernatural claims.

Claims

The moral value of a being is equal to that of its potential

It is often misused this way, with the deontological premise that something/someone's moral value is equal to its potential.

P1. X's moral value is equal to X's potential.
P2. Rocks have the potential to be sentient with the right random arrangement of atoms, even if it might only happen once in a googleplex to the googleplex power lifetimes of the universe.
C1. Rocks' moral value are equal to that of sentient beings.

That is a reductio that shows glaringly the obvious problems with such a premise--leading to conclusions where everything and anything has inconceivable amount of moral value.
However, it is often used in more subtle ways that are not so obviously absurd, such as:

P1. X's moral value is equal to X's potential.
P2. Early fetuses have the potential to become babies.
C1. Fetuses have moral value equal to that of babies.

But you can push it a step further:

P1. X's moral value is equal to X's potential.
P2. Sperm have the potential to become babies.
C1. Sperm have moral value equal to that of babies.

And even further:

P1. X's moral value is equal to X's potential.
P2. Food has the potential to become sperm, which has the potential to become babies.
C1. Food has moral value equal to that of babies.

And so on.

'Potential' is an arbitrary value that is meaningless unless tied to a non-arbitrary moral basis (such as interests of sentient beings).

For example, if it was about potential to experience a good future (and therefore happiness), it could be said:

P1. Early fetuses have Y amount of potential to become babies and experience a fulfilling and happy future growing up.
P2. By killing a fetus, as a consequence you would deprive the Y amount of potential for that happiness to happen, leaving an -Y amount of potentially less happy future (Y amount of potential for happiness taken away).
C1. Killing the fetus is -Y amount of potentially wrong.

In this case potential takes the meaning of probability, and therefore relies on another value system to have meaning. While before, potential was itself the value system, which is meaningless.

Potential as the bases of morality being an arbitrary and meaningless value system can sometimes be tricky to see, as people relying on 'potential' for their argument often use it in a context where potential could make sense, and their statement makes sense at face value, since the stance taken would be sound if 'potential' was used with the meaning 'probability' for another value system--but it is ultimately not, as potential by itself is arbitrarily used to make any conclusion happen without actually taking probability into account as a factor that matters.

A being's potential to be/become something is reasonable probability that it is/will be, and therefore it has to be given the benefit of the doubt that it is/will become that something

Another way people use the argument from potential, that is not equating the moral value of something with its potential, is by giving something reasonable probability to meet its potential (whichever potential that may be), and therefore assigning it the benefit of the doubt that follows.

For example:

P1. If X has the potential to be/become Y, X has reasonable probability that it is/will be Y, therefore X should be given the benefit of the doubt that it might be/become Y when considering X's moral value.
P2. Rocks have the potential to be/become sentient with the right random arrangement of atoms, even if it might only happen once in a googleplex to the googleplex power lifetimes of the universe.
C1. Rocks have reasonable probability that they are/will be sentient, therefore rocks should be given the benefit of the doubt that they are/will be sentient when considering the moral value of rocks.

This reasoning is inherently inconsistent, since the reasonable probability threshold required to give something the benefit of the doubt has to be defined and reasoned for the potential to have any meaning, or anything applies to 'reasonable probability' and should be given the benefit of the doubt.

If the line is drawn at 1% chance for the potential to be true, then C1. does not follow, as rocks being/becoming sentient has an astronomically lower chance of being true than 1%.

If the line is drawn at 10^-googleplex to the googleplex power lifetimes of the universe, then rocks should be given the benefit of the doubt to be/become sentient, as well as a universe of magical dragons existing inside each of your cells should be given the benefit of the doubt for it to be true, as well as anything whatsoever--since anything is scientifically possible.

When people say 'potentially' they are often setting up an arbitrary threshold of what they consider reasonable probability, but ultimately an undefined and moving goal post that suits their position.