The principle of causality is one of the primary propositions known to people in their ordinary lives. This principle states that ‘everything has a cause’. It’s one of the necessary rational principles; a human being finds at the heart of his nature a motive that makes him attempt to explain the things he encounters, and to justify the existence of such things by disclosing their causes. This motive is inborn in human nature (and it may also be present in a number of animals; they instinctively pay attention to the source of a motion in order to know its cause, and they also search for the source of a sound, again in order to know its cause).
That’s why we’re always faced with the question ‘why?’. This question is raised concerning every existence and every phenomenon of which we’re aware, such that even if we don’t find a specific cause, we believe there’s an unknown cause that produced the event in question.
The following things depend on the principle of causality:
- Demonstration of the objective reality of sense perception
- All scientific theories and laws that are based on experimentation
- Inference and its conclusions in any philosophical or scientific field
Without the principle and laws of causality, it would be impossible to demonstrate the objectivity of sense perception, or any scientific theory or law.
Furthermore, it would be impossible to draw any inference in any field of human knowledge on the basis of any kind of evidence. This point will soon be clarified.
Causality and the Objectivity of Sense Perception
Sense perception is nothing but a form of conception. It’s simply the presence of the form of the sensed thing in the senses. It doesn’t have the character of a true disclosure of external reality.
That’s why in the case of certain illnesses, we may have sense perceptions of certain things (hallucinations), without assenting to the existence of those things. So sense perception isn’t a sufficient ground for assent, judgement, or knowledge concerning objective reality.
The problem we then face is that if sense perception isn’t itself evidence for the existence of sensible things, then how can we assent to the existence of their objective reality? The answer is revealed in light of our study of the theory of knowledge. It’s this: the assent to the existence of an objective reality for the world is a primary necessary assent. For this reason, it doesn’t require evidence.
However, this necessary assent indicates only the existence of an external reality for the world in general; the objective reality of every specific sense perception is not known in a necessary manner. Therefore, we need evidence to prove the objectivity of every specific sense perception. This evidence comes in the form of the principle and laws of causality.
The perception of a specific thing reveals, in accordance with the principle of causality, the existence of an external cause for that perception (the objective existence of the thing perceived causes the perception). Without this principle, sense perception (or the presence of a thing in the senses) can’t reveal the existence of that thing in any other sphere.
Because of this, in specific cases of illness, we may perceive certain things (hallucinations), or imagine that we see them, without discovering an objective reality for them. This is because the principle of causality doesn’t prove the existence of their objective reality, as long as it’s possible to explain them by the specific case of illness (the illness is then believed to cause the perception).
Without the principle of causality, those hallucinations would’ve been considered real and as having external reality.
From this we can draw the following three propositions:
- Sense perceptions by themselves don’t disclose the existence of objective realities, because they’re conceptions and it’s not the task of conceptions (regardless of their kind) to give true disclosures.
- Knowledge of the existence of a reality for the world in general is a necessary and primary judgement that doesn’t require evidence (it doesn’t require prior knowledge); this is the point separating idealism from realism (this is why we naturally believe the world around us exists).
- Knowledge of an objective reality for specific sense perceptions is acquired only in light of the principle of causality.
Causality and Scientific Theories
Scientific theories in various experimental and observational fields are in general primarily dependent on the principle and laws of causality. If causality and its proper order are eliminated from the universe, it becomes very difficult to form a scientific theory in any field. To clarify, we shall point out some philosophical causal principles on which science rests. These are the three main principles:
The principle of causality, which asserts that every event has a cause
The principle of necessity, which asserts that every cause necessarily produces its natural effect, and that it’s impossible for effects to be separated from their causes
The principle of harmony, which asserts that every natural group that’s essentially harmonious must also be harmonious with respect to its causes and effects.
For example, in light of the principle of causality, the radiation emitted from a radium atom has a cause, which is the unstable internal division of the atom. Further, in light of the principle of necessity, we find that this division necessarily produces the specific radiation when the necessary conditions are fulfilled. The presence of these conditions and the production of this radiation are inseparable (the presence of an unstable nucleus necessarily produces radiation).
The principle of harmony is the basis of our ability to generalize the phenomenon of radiation and its explanation to all radium atoms.
Thus, we say that as long as all the atoms of this element are essentially in harmony, they must also be in harmony with respect to their causes and effects. If scientific experimentation finds radiation in a number of radium atoms, it becomes possible to assert that radiation is a common phenomenon of all similar radium atoms, given the same specific circumstances (that’s why we say that ‘all radium atoms emit radiation’).
It’s clear that the principle of necessity and the principle of harmony are the result of the principle of causality. If there were no causality in the universe, and things happened haphazardly by chance, it wouldn’t be necessary to assume that whenever there’s a radium atom, radiation exists. It wouldn’t be necessary that all atoms of this element share the same specific radiational phenomena. Rather, if the principle of causality is excluded from the universe, it would be proper to say that radiation simply pertains to one atom (the one seen in the experiment) and not necessarily to another one of the same kind, due to haphazardness and chance. The acceptance of necessity and harmony are thus attributed to the principle of causality.
Now let’s go back to science and it’s theories. We can clearly see that all scientific theories and laws depend on the principle and laws of causality. If this principle weren’t taken as a fixed philosophical truth, it would be impossible to establish a theory and to erect a general and comprehensive scientific law.
That’s because experiments performed by scientists in their labs can’t cover all parts of nature. Rather, experiments only cover a limited number of parts that are essentially in harmony. The experiment finds that such parts share a specific phenomenon. When scientists are certain of the soundness, precision, and objectivity of their experiments, they can postulate theories or general laws applicable to all parts of nature that resemble the subjects of their experiments.
This generalization, which is a basic condition for establishing any scientific fact, can’t be justified without the laws of causality (the law of harmony in particular, which asserts that every group that’s essentially in harmony must also be in harmony with respect to its causes and effects).
Therefore, if there weren’t causes and effects in the universe, and if things occurred by pure chance, it wouldn’t be possible for scientists to say that what is confirmed in their own labs is generally applicable.
Let’s illustrate this with an example. Suppose there was a scientist who proved by experimentation that things expand when heated. He obviously couldn’t use every object in the universe in his experiments. So he performed his experiments on a select number of various objects, such as pieces of iron or wheels made of rubber. At the end of his experimentation, he still couldn’t escape the following question: ‘Since you haven’t covered every particular object, how can you believe that pieces of iron or rubber wheels other than those you have tried will also expand by heat?’
The answer to this question is the principle of causality. Since the mind doesn’t accept haphazardness and chance, and rather explains the universe on the basis of causality and its laws (including those of necessity and harmony), it finds in limited experiments a sufficient ground for accepting a general theory (which in this example is thermal expansion)
Thus we know that positing a general theory isn’t possible without starting from the principle of causality. This is why this principle is the primary foundation of all experimental sciences and theories. In short, experimental theories don’t acquire a scientific character unless they’re generalized to cover fields beyond the limits of particular experiments, and are given as a general truth. They can’t be given as such, except in light of the principles of causality. Therefore science, in general, must consider the principle of causality and the closely related principles of necessity and harmony as fundamentally admitted truths, and accept them prior to all experimental theories and scientific facts.
Causality and Inference
The principle of causality is the foundation on which all attempts of demonstration in all spheres of human thought rest. This is because demonstration by evidence for a certain thing means that, if the evidence is sound, it’s a cause for the knowledge of the thing. Whenever we try to prove a certain truth with a scientific experiment, a philosophical law, or a simple sense perception, we only attempt to have the proof so it may serve as a cause for the knowledge of that truth.
If it weren’t for the principles of causality and necessity, we wouldn’t be able to do so. Why? Because if we discounted the laws of causality and didn’t accept the necessity of the existence of specific causes for every event, there wouldn’t be any link between the evidence on which we rely and the truth we attempt to acquire by virtue of the evidence. Without the principles of causality, it becomes possible for the evidence to be sound without leading to the required result, since the causal relation between the pieces of evidence and the results, or between the causes and the effects, is broken off.
Thus, it becomes clear that every attempt at demonstration depends on the acceptance of the principle of causality; otherwise, it’s a wasteful and useless attempt. Even the demonstrations for the disproof of the principle of causality, which is attempted by some philosophers and scientists, also rests on the principle of causality.
For those who attempt to deny this principle by resorting to certain evidence wouldn’t make such attempts had they not believed that the evidence on which they rely is a sufficient cause for the knowledge of the falsehood of the principle; this itself would be a literal application of this principle.
Mechanics and Dynamics
This leads to the following three conclusions:
- It’s not possible to prove or to demonstrate empirically the principle of causality, since the senses can’t acquire an objective character except in light of this principle. We prove the objective reality of our sense perceptions on the basis of the principle of causality. Therefore it’s not possible that this principle depends on the senses and relies on them for its demonstration. It’s a rational principle that people accept independently (without depending on external senses).
- The principle of causality isn’t an experimental scientific theory. Rather, it’s a rational philosophical law above experimentation, because all scientific theories depend on it. This becomes clear after knowing that every scientific conclusion that relies on experimentation faces the problem of generality and comprehensiveness. The problem is that the experiment on which the conclusion rests is limited. How could it then, by itself, be evidence for a general theory? We found that the only solution to this problem is the principle of causality (it’s evidence for the generality and comprehensiveness of the conclusion). Thus, if we assume that the principle of causality itself rests on an experiment, it becomes necessary that we face the problem of generality and comprehensiveness once again. An experiment can’t cover the whole universe; how then would it be considered evidence for a general theory? When encountering this problem with respect to the various scientific theories, we solve it by resorting to the principle of causality, since this principle is sufficient evidence for the generality and comprehensiveness of the conclusion. But if this principle itself is considered experimental and the same problem is encountered with respect to it, we’ll be totally unable to solve this problem! Therefore the principle of causality must be above experiments, and it must be a fundamental principle of experimental conclusions in general.
- It’s not possible to give any kind of evidence for the disproof of the principle of causality. That’s because every attempt of this kind entails an admission of this principle. Therefore, this principle is fixed prior to any evidence given by human beings.
These conclusions can be summarized as follows. The principle of causality isn’t an experimental principle. Rather, it’s a necessary rational principle. In light of this, we can distinguish between mechanics and dynamics, and between the principle of causality and the principle of indeterminacy.
The mechanical explanation of causality rests on the basis of causality as an experimental principle. According to mechanical materialism, this principle is nothing but a material relation between material phenomena in the experimental field and is discovered by scientific methods.
That’s why it’s natural that mechanical causality collapses if experimentation fails in some scientific fields to disclose the causes and agents behind the phenomenon in question. That’s because this kind of causality is not attained except on an experimental basis. If experimentation works against it, and practical application doesn’t prove it, then it falls short of scientific confidence and consideration.
However, according to our view of causality, which asserts that causality is a rational principle above experimentation, the situation is completely different with regard to various aspects. First, causality isn’t limited to the natural phenomena that appear in the experiment. Rather, it’s a general law of existence at large, which includes natural phenomena, matter itself, and various kinds of things that lie beyond matter. Second, the cause whose existence is confirmed by the principle of causality doesn’t have to be a material thing, or subject to experimentation. Third, just because some experiments can’t find a specific cause of a certain development or of a certain phenomenon doesn’t mean a failure on part of the principle of causality, because this principle doesn’t rest on experimentation (which would’ve made it break in the case of the absence of experimentation). In spite of the failure of experimentation to discover the cause, philosophical confidence in the existence of such a cause remains strong, in accordance with the principle of causality. The failure of experimentation to discover the cause is then due to two things: either to the fact that experimentation is limited and doesn’t extend fully to the material reality and occurrence of specific attachments, or to the fact that the unknown cause lies outside empirical thought and is beyond the world of nature and matter.
Based on the above, we can distinguish basic differences between our idea of the principle of causality and the mechanical idea of this principle. We can also see that doubts raised concerning this principle are only due to interpreting it according to the deficient mechanical notion.
The Principle of Causality and Quantum Physics
In light of the conclusions drawn above regarding the principle of causality, we can defeat those ‘strong attacks’ that were waged in quantum physics against the law of necessity, and consequently against the principle of causality itself.
There was a tendency in the field of quantum physics which asserted that the necessary regularity stressed by causality and its laws can’t be true on the subatomic level.
In other words, causality may work properly on the level of normal ‘naked eye’ physics, but everything appears different if we try to apply the principle of causality to the subatomic world. That’s why Heisenberg declared that it’s impossible for us to measure with precision the quantity of the motion of a particle and to determine at the same time the position of this particle in the wave related to it, in accordance with the positive mechanics called for by Louis de Broglie. The more precise the measurement of the particle’s position, the more is this measurement a factor in the readjustment of the quantity of motion, and consequently in the readjustment of the velocity of the particle in an unpredictable manner. Further, the more precise the measurement of the motion, the more indeterminate the position of the particle becomes.
Thus, physical events in the subatomic sphere can’t be measured unless they involve some unmeasurable disorder. The more profound our precision of the scientific measurements, the more distant we become from the objective reality of those events. This means that it’s not possible to separate a thing observed in microphysics from the scientific instrument used by the scientist to study that thing.
Similarly, it’s not possible to separate that thing from the observer himself, since different observers working on the same subject with the same instrument may achieve different measurements. With this, the idea of indeterminacy arose; this idea is apparently in full contradiction with the principle of causality and with the basic rules that governed physics previously.
Attempts were made to replace the principle of necessity by what are called ‘uncertainty relations’ or ‘laws of probability’ advocated by Heisenberg, who insisted that science can’t make predictions with certainty when considering a subatomic particle; the utmost we can do is form a probability.
But all these scientific doubts and suspicions that scientists raised in quantum physics are based on a certain notion of the principle of causality that disagrees with our notion of this principle.
We don’t wish to disagree with these scientists over their experiments, nor do we ask them to overlook and abandon the discoveries made by means of these experiments. Furthermore, we don’t intend to minimize the value and importance of such discoveries. Rather, we differ from those scientists in our general notion of the principle of causality. Because of this difference, all the mentioned attempts to destroy the principles of causality become insignificant.
Put in more detail, if the principle of causality was a scientific principle that rests on experimentation and observation in ordinary fields of physics, it would be dependent on experimentation for its demonstration and generality. So if we can’t achieve clear applications of it in the quantum field and can’t discover a necessary order in this field that rests on the principles of causality, then it would be our right to doubt the value of this principle and the extent of its soundness and generality.
But we have already shown that the applicability of the principle of causality to the ordinary fields of physics, and the belief that causality is a general order of the universe, isn’t based solely on the results of experimental evidence, and that the principle of causality is a necessary principle above experimentation.
If this were not so, no natural science would be possible. If this becomes clear to us, and we give the principle of causality its natural place in the chain of human thought, our inability to apply it experimentally in some scientific fields (and our failure to discover by scientific methods the complete necessary order in these fields) shouldn’t shake our belief in this principle.
All observations gathered by scientists in their microphysical experiments don’t show that scientific evidence has disproved the principles of causality in this field (which is just one of many scientific fields).
It’s clear that the lack of scientific and experimental capabilities doesn’t affect the principle of causality, neither in part nor as a whole, since this principle is necessary and above experimentation. There are, then, two explanations for the failure of scientific experiments in their attempt at grasping the mysteries of the necessary order of particles.
The first is a deficiency in the scientific methods and an unavailability of experimental instruments that give us the opportunity to look over all material conditions and circumstances. A scientist may work on the same subject with the same instrument on a number of occasions. Yet, he may reach different results, not because the subject of his work is free from any necessary order, but because the available experimental instruments are insufficient to disclose to him the exact material conditions whose differences lead to the differences among the results. It’s natural that experimental instruments concerning subatomic fields and quantum events are more deficient than experimental instruments employed in other physical fields (that are clearer and less mysterious).
The second is the effect produced in the subject by the scientific measurements and instruments themselves. Scientific instruments may reach the highest levels of precision, perfection, and profundity, yet still we won’t be able to solve this problem (because the more precise our measurement of the particle’s velocity, the less precise our measurement of its location will be). We find ourselves confronted with physical events that we can’t measure without introducing in them an immeasurable disorder from our instruments.
Both of these factors can explain the failure of scientific experimental instruments and observations in this field. All of this confirms our inability to view the necessary order governing subatomic particles and their motion, and to predict with precision the paths that these particles follow. This, however, doesn’t disprove the particles’ dependence, and nor does it justify the introduction of indeterminacy in the material realm, and nor does it justify the elimination of causal principles from the universe.
The following sources are used to prepare the above article.
1. Ayatollah Baqir Al-Sadr’, Our Philosophy.