Lecture Series: Lecture 15: Philosophy and Science

Perhaps the first thing to say about the relationship of Christianity and science is that events do not interpret themselves. Science is not a value neutral enterprise. Some worldview is logically anterior to the events in question and serves as the interpretive paradigm by which the events are understood, their insights appropriated and applied.

This is why any understanding of science must first answer fundamental questions, perhaps best understood as the "philosophy of science."

This is where we begin. We must first develop a reasonable philosophy of science before we can rightly interpret the insights afforded to us by science. We will organize this by discussing certain fundamental questions in the philosophy of science.

Question 1: Is all knowledge discerned through the five senses? Is strict empiricism possible?

Answer: No! If there is anything that the history of philosophy has demonstrated, it is that there must be some content to our understanding that comes to us a priori (prior to sense experiences). This knowledge is necessary in order for us to make sense of the experiences we have. Some philosophers refer to this content of knowledge as features our our "noetic structure" (mind structure). Others talk about them as "properly basic beliefs." The point is that some ideas are innate, hard-wired into us by virtue of the way the mind is built to function. An example of this kind of knowledge would be mathematical and logical principles. Kant included time/space relations and causation in this content of a priori truths we simply know about. Others include moral law. And still others would suggest that knowledge of God is also a feature of our a priori knowledge.

But why is it the case that it is impossible for all our knowledge to come from our sense experiences? Well, think about it. What is the problem with the statement, "all our knowledge comes from sense experiences?" Clearly the statement, "all our knowledge comes from sense experiences" did not itself come from sense experiences. One could experience everything in the universe and it still would not bring down the philosophical conclusion that "all knowledge is restricted to the domain of the five senses." Such an idea is not physically discerned. Clearly not all ideas are derived from experiences. Ideas are used to interpret experiences in many cases.

Another point here: Can you even imagine shutting off all your senses? What would that mean for you? Could you really have knowledge? Now consider the opposite question: What would it mean if you had a constant stream of sense experiences, but no "operating system" to process the experiences? Surely knowledge would be impossible in either case. But of course this entails that there are some things we know about a priori. And surely this is one of the conclusions of philosophical history--namely, that it is impossible to imagine human knowledge without a harmonious relationship between the knowledge we learn from experience and the knowledge we possess prior to experience.

Question 2: Is science a value neutral exercise? (an exercise totally unclouded by bias)

Answer: No! This point will relate somewhat to the previous point. The fact is that science and scientists presuppose things about the nature of reality. And these presuppositions color everything about the conclusions they draw from the science lab.

Here is a short list of principles scientists take for granted as true, but without any scientific proof of their existence:

1. The universe is intelligible.

2. The rational structure of the mind relates to a rational structure in the world. (In short, I'm not just perceiving things; I'm actually figuring out how the universe really works)

3. The principle of causation. (We can thank David Hume for moving this one out of the realm of observational truth and into the realm of presupposition.)

4. Knowledge is possible.

5. The inductive principle holds because of the uniformity of nature (the idea that the future will be like the past... i.e. fire will burn in the future because it has in the past).

Every one of these principles has in common the fact that they are not learned by experiences of the world. They are assumptions about the world imposed upon our experiences and employed in order to give meaning to our experiences. I'd like to know how the scientist is going to go about demonstrating in a laboratory or field research that the universe is intelligible without first assuming that the universe is intelligible in order to demonstrate that the universe is intelligible.

Here is the simple point: Every scientist is a philosopher and every philosopher is a scientist. The two are inextricably linked. The key is to be precise about what knowledge comes from our observations of the universe and what knowledge comes from other sources. It is totally irresponsible and unfair for any scientist to suggest that philosophers have nothing to say; and it is equally irresponsible for any philosopher to suggest that scientists have nothing to say.

Question 3: Since all science proceeds on the assumption of causation, is there good reason to trust this assumption?

What if the world is just a random collection of events and the order we perceive is merely a human phenomenon? In other words, perhaps the idea that the world is knit together by a series of causal connections is only an idea subjectively maintained in the mind of man. Can we prove causation?

According to the Scottish philosopher David Hume, causation cannot be proved. He argues that our perceptions of the world are divided into impressions and ideas. Impressions are the lively encounters we have with the world (things imprinted on the mind via our senses). Ideas are what the mind does to interpret and string these experiences together. An example here: We have impressions of horses, and then we have impressions of horns. We put the two together to form the idea of Unicorns. But of course we have no simple impression of Unicorns; Unicorn is a mere idea we formed from sense impressions.

Now let's go a bit deeper: We experience events that follow one another in the world. For example, we hear a rooster crow and then the sun comes up. We hit a billiard ball into another and then the second ball moves. Here is our dilemma: How can we know that there is any causal relationship between the events we perceive in sequence? We have simple impressions of the events, but not the principle of cause and effect. All we have experienced is one event following another. For all we know, there is no causal connection between events. Perhaps what is happening is that we are imposing the idea of causation on events that are not really related. Every time I hit a billiard ball it causes the movement of the other, but is it at least possible that tomorrow I will hit a billiard ball and the second ball will remain motionless when struck by the first? All I know for sure is that every time I've experienced the first ball hitting the second, it moved, but does that prove there is a magical principle called causation holding the universe together? What if causation is not "in the world," so to speak; what if it is only in me? In other words, it is at least possible that the universe is a wholly random collection of events, and that the belief that events are ordered causally is something I am "doing to it."

Hume acknowledges that we live as if there is such a thing as causation, and it has "worked" for us to this point. But his point is that it cannot be proven, in which case a person could theoretically live as if it isn't real.

The implications of this are startling! Essentially, Hume suggests that the very foundational principle of science is subject to a serious and debilitating skepticism. The question must be asked, "why do science if we can't know for sure that we are discovering the nature of the world?" Surely all of science proceeds on the opposite assumption--namely, that the reason we study things like the human body is so that we can figure out how it actually works, and not merely to delve more deeply into our perceptions about how it works.

Now if Hume's conclusion is that causation itself is to fit in the category of a priori truths, or properly basic truths, then he is merely acknowledging that some truths are known without reference to experience and they are confirmed by their pervasive use and capacity to guide experience. Obviously we don't say that we learned about logic through experience, but surely logic guides us in interpreting experience. Perhaps causation is something like logic in this regard. It is not perceived by the senses, but it informs and governs what the senses "bring in."

What else can be said by way of response to Hume? If he is saying that we cannot know causal connections between events and thus cannot know reality--that we are little more than human "perceivers," then his view seems self-refuting. In essence, he would be saying that we cannot know anything of a philosophical nature for sure. But of course, to say that we cannot know anything of that kind is to state something he thinks he knows.

And finally, one can ask, as have Geisler and Bocchino, "Did Hume assume causation in order to follow a path of cause and effect reasoning to arrive at his conclusion?" Did his thinking have a causal relationship to his doubt? If it did, then even the act of his thinking about causation affirms causation--that is, to question causation he has had to employ it, which is self-refuting as well.

Question 4: Where would philosophical skepticism lead us?

If Hume is right and we are only human "perceivers" who cannot know for certain that our ideas have any relationship to the "real world," then perhaps we should all become skeptics. The skeptic claims that we cannot have certainty about anything other than the irreducible brute facts of experience. Anything the mind does to construct ideas from this raw material is grounded only in our thinking, and perhaps not in reality. In the end, we have cause to doubt our beliefs about the world.

Now aside from the fact that even this is self-refuting (after all, if we can doubt all ideas in the mind, then surely we can also doubt the idea that all ideas are doubtful), let us consider what the idea would lead to if it could be true.

If we can doubt all ideas, then relativism must emerge. And the reason is simple: no reliable ideas means that all ideas are equally unreliable. All ideas have the same value, or lack thereof.

If all ideas have the same quality of unreliability, then none of them really matter. No idea can be truer or better than any other, which in the end must mean that all ideas are worthless--a mere chatter of pointless perspectives. Thus nihilism emerges, which is the philosophical position that the world is meaningless and nothing matters in the end.

If nothing really matters, then how is one to cope with such an idea? The answer is hedonism. The only real coping mechanism as a mere sensing being is to minimize the pain introduced to those senses and to maximize the pleasure that any stimulation of them might provide.

Thus, if a person is a hedonist, it could be because he is a skeptic. Perhaps he believes that we cannot know about God and morality and human dignity and the afterlife. Curiously many who believe such things default to a lifestyle of temporal hedonism.

5. Does Quantum physics indicate that we cannot trust the principle of causation?

Some scientists have noted that the indeterminacy principle in physics suggests that we cannot know whether causation operates at the most foundational level in the physical world--that is, at the atomic level. Upon the disintegration of the atomic nucleus, particles are generated and emitted that did not exist before this event. It seems that they just pop into existence without any direct cause. Thus, some have suggested that causation is dethroned by such phenomena.

But the curious thing is that causation was a precondition for discovering the indeterminacy principle. Scientists were asking, from whence comes these particles? And they discovered that the cause is unknown. Many Christians scientists and philosophers ask simply, "why believe that the particles generated in radioactive decay come from nothing?" "Why not believe that they simply have an unknown cause?"

The implications of the belief that there is no such thing as operational causation at the foundational level of existence are staggering. If causation does not exist at that level, then perhaps it does not exist at any level, in which case all science would conceivably be rendered meaningless again.

And consider the implications in ethics. What if my decisions in ethics do not flow from any causal factors, but are spontaneously generated and thus wholly unpredictable? I can just see new defenses for criminal behavior sounding something like this: "Your honor, I am not guilty because causation does not reign in nature, and thus I am not the cause of my behavior. My behavior happens to me and not the other way around, your honor!"

In conclusion, it must be clear that science is not a worldview-neutral exercise. Science itself requires a worldview robust enough to support its search for truth. Obviously it undermines the search for truth to suggest either that there is no truth to be found or if there is we will never know it.