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Does Scientific Progress Consist in Increasing Knowledge or Understanding?
Abstract
Bird (2007) argues that scientific progress consists in increasing knowledge. Dellsén (2016a)
objects that increasing knowledge is neither necessary nor sufficient for scientific progress,
and argues that scientific progress rather consists in increasing understanding. Dellsén also
contends that unlike Bird’s view, his view can account for the scientific practices of using
idealizations and of choosing simple theories over complex ones. I argue that Dellsén’s
criticisms against Bird’s view fail, and that increasing understanding cannot account for
scientific progress, if acceptance, as opposed to belief, is required for scientific understanding.
Keywords
Epistemic Approach, Knowledge, Noetic Approach, Scientific Progress, Understanding
Park, Seungbae (2017). “Does Scientific Progress Consist in Increasing Knowledge or
Understanding?”, Journal for General Philosophy of Science 48 (4): 569–579.
Acknowledgement: This paper improved a lot thanks to the insightful comments from
anonymous referees and Dr. Beisbart.
Seungbae Park
Ulsan National Institute of Science and Technology
Republic of Korea
nature@unist.ac.kr
1. Introduction
Alexander Bird (2007) defends the epistemic approach to scientific progress, according to
which scientific progress consists in increasing knowledge. Finnur Dellsén (2016a) proposes
an original alternative approach to scientific progress which he calls the noetic approach.
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According to the noetic approach, scientific progress consists in increasing understanding. He
argues that the noetic approach is superior to the epistemic approach. This paper aims to
defend the epistemic approach from Dellsén’s criticisms
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and to criticize the noetic approach.
There are other approaches to scientific progress in the literature. They are the semantic
approach (Niiniluoto, 1980; 2014) and the problem-solving approach (Kuhn, 1962/1970;
Laudan, 1977; 1984), but these approaches fall outside the scope of this paper.
The outline of this paper is as follows. In Section 2, I spell out the epistemic and noetic
approaches, and then reply to referees’ objections to the epistemic approach. In Section 3, I
attempt to refute Dellsén’s contention that there can be scientific progress and an increase in
understanding, even without any accumulation of knowledge. In Section 4, I attempt to
confute his contention that even if there is an accumulation of knowledge, there can be no
scientific progress and no increase in understanding. In Sections 5 and 6, I reply to his
objections that the noetic approach accounts for, while the epistemic approach cannot, the
scientific practices of using idealizations and of choosing simple theories over complex ones.
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‘Noetic’ comes from the Greek ‘nous’ which means understanding (Dellsén, 2016: 72, footnote 2).
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See Darrell Rowbottom (2010), Ilkka Niiniluoto (2015), and Juha Saatsi (2016) for other criticisms against the
epistemic approach.
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2. Epistemic and Noetic Approaches
Bird says that “an episode in science is progressive when at the end of the episode there is
more knowledge than at the beginning” (2007: 64). He also says that “progress is made when
certain means to an end are achieved” (2007: 83). So the epistemic approach comes down to
the suggestion that scientific progress consists in increasing knowledge or in achieving a
means to increase knowledge. Let me call the second part of the epistemic approach the
means-end thesis. It implies that an episode is progressive, even if there is no more
knowledge at the end of it than there was at the beginning of it, insofar as it paves the way for
the production of knowledge in subsequent research. Suppose for the sake of argument that
the history of science was filled with discarded theories, that past scientists did not generate
knowledge, including observational knowledge, and that they kept researching despite
repeated failures. Even so, they made progress, as long as their practices will contribute to the
generation of knowledge in subsequent researches.
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How would critics respond to the means-end thesis? They might object that the thesis is
too permissive (referee). Not everything that promotes the accumulation of scientific
knowledge counts as scientific progress. For example, technological advances and increased
funding for scientific research promote the growth of scientific knowledge, but hardly count
as scientific progress in the relevant sense. It is not clear on what grounds the means-end
thesis excludes those developments that promote knowledge but do not count as scientific
progress.
My response to this objection is to point out that the debate over scientific progress is
restricted to those episodes that involve cognitive changes. Increased funding is not an
episode that involves a cognitive change. Unlike increased funding, confirming a hypothesis
is an episode that involves a cognitive change. So increased funding might be called a non-
cognitive episode; confirming a hypothesis might be called a cognitive episode. Participants
in the debate over scientific progress are in the business of determining whether a cognitive
episode is progressive or not, not whether a non-cognitive episode is progressive or not. In
light of this observation, let me formulate the epistemic approach more precisely as the view
that a cognitive episode in science is progressive, if and only if it involves the increase in
knowledge or the acquisition of a means to increase knowledge.
Critics might also object that the means-end thesis makes it difficult to discriminate,
within the whole of the activities that are referred to as ‘scientific inquiry,’ the episodes that
count as instances of cognitive progress (another referee). Indeed, in light of the means-end
thesis, far too many things seem to count as progress. Epistemists would view the mere fact
that scientists keep researching despite repeated mistakes as progressive. Given how broad
the notion of progress becomes in view of the means-end thesis, it seems legitimate to ask
what part or phase of scientific inquiry would not count as progress on the epistemic
account.
My response to this worry is to admit that there can be an epistemological problem
over whether a cognitive episode does or does not serve as a means to obtain knowledge.
This epistemological problem, however, does not denigrate the means-end thesis. To use an
analogy, the correspondence theory of truth holds that a statement is true if and only if it
corresponds to a state of affairs. There can be an epistemological problem over whether a
particular statement corresponds to a state of affairs or not. This epistemological problem,
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Bird conjectures, a referee points out, that “the relevant developments that promote knowledge will
themselves be knowledge” (2007, 84). In my view, however, Bird seems to mean gathering observational
knowledge by ‘the relevant developments.’ In any event, the epistemic approach requires only the mean-end
thesis.
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however, does not denigrate the correspondence theory of truth. It is one thing to propose a
criterion to distinguish between true and false statements; it is another whether we have
enough evidence or not to tell whether a particular statement is true or false. Similarly, it is
one thing to propose a criterion to distinguish between progressive and non-progressive
episodes; it is another whether we have enough evidence or not to tell whether a particular
episode is progressive or non-progressive. The referee’s objection, however, shows that when
epistemists claim that a cognitive episode is progressive, they have the burden to show that
there is an increase in knowledge in the episode, or that the episode serves as a stepping stone
for the growth of knowledge in subsequent research.
Let me turn to Dellsén’s conception of scientific understanding. He says that an “agent
has partial scientific understanding of a given target just in case she grasps how to correctly
explain and/or predict some aspects of the target in the right sort of circumstances” (2016a:
75). An explanation is “correct even though it appeals to theories that are strictly speaking
false, e.g. idealizations and simplifications, provided that those theories help identify the
explanatorily relevant factors on which the explanandum depends” (Dellsén, 2016a: 75). In
addition, “the explanatorily/predictively essential elements of a theory must be true in order
for the theory to provide grounds for understanding” (Dellsén, 2016a: 73, footnote).
The foregoing conception of scientific understanding is built into the noetic approach,
according to which “scientific progress consists in increasing understanding,” and “an
episode in science is progressive precisely when scientists grasp how to correctly explain or
predict more aspects of the world at the end of the episode than at the beginning” (Dellsén,
2016a: 73). The noetic approach does not embed the means-thesis (referee). Dellsén states
explicitly that “since nearly anything can promote progress, we must be careful not to
confuse scientific progress itself with the promotion of such progress” (2016a: 73). So he
would not say that an episode is progressive on the grounds that a means to increase
understanding is gained in the episode.
Let me apply the noetic approach to the series of the three theories of diseases in the
history of science. The humoral theory, the miasma theory, and the germ theory hold,
respectively, that a disease results from an imbalance of the four humors, from a noxious air,
and from germs. If the germ theory is true, the humoral theory and the miasma theory failed
to identify the explanatorily relevant factors. The noetic approach, however, implies that there
was scientific progress in the transition from the humoral theory to the miasma theory,
provided that the miasma theory predicted more phenomena than the humoral theory.
According to the noetic approach, scientific progress requires not both increasing
explanations and predictions, but increasing explanations or predictions.
3. Is Knowledge Necessary for Scientific Progress?
Philip Kitcher (2002), Peter Lipton (2004), and Stephen Grimm (2006, 2014) claim that
belief and justification are essential components of understanding. Dellsén, however, rejects
their view, arguing that understanding requires neither belief nor justification, and that in
certain cases in science, there is no increase in knowledge, but there is an increase in
understanding, and the increase in understanding matches scientific progress. In other words,
what is necessary for scientific progress is not increasing knowledge but increasing
understanding. I flesh out and criticize Dellsén’s argument for this contention in this section.
Dellsén argues that belief is not required for understanding, and that scientific progress
consists in increasing understanding, so increasing knowledge is not necessary for scientific
progress. So we need to examine how he argues that understanding does not require belief.
He (2016b: 10) appeals to L. Jonathan Cohen’s (1992) distinction between belief and
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acceptance. For Cohen, to believe p is to feel it to be true, and to accept p is to adopt the
policy of including p “among one’s premises for deciding what to do or think in a particular
context” (1992: 4). To use Cohen’s example, a lawyer may accept that her client is innocent
in court. Once she accepts the proposition, she can infer that the prosecutor’s witness is not
reliable, and can speak to the judge accordingly. Just as the lawyer merely accepts the
proposition, so a physicist may merely accept string theory, and then use it “to explain any
fundamental physical phenomena just as well as someone who also believes string theory”
(Dellsén, 2016b: 11). It is not required that agents believe that theories are true – they “may
merely assume or accept that they are true for the purposes of explanation and or prediction”
(Dellsén, 2016a: 76). In short, “understanding something may merely involve treating certain
propositions or theories as given in the context of explaining something, as opposed to being
disposed to feel that the propositions or theories are true” (Dellsén, 2016b: 10).
Contrary to what Dellsén claims, however, scientific understanding does require belief.
In science, a tragic result may occur, if understanding lacks belief. Imagine that you are a
scientist, and that you tested the hypothesis that the low intake of folic acid during pregnancy
increases the chance of having premature babies. You studied one hundred pregnant women.
The half and the other half of them took, respectively, less than two hundred micrograms and
more than three hundred micrograms of folic acid a day during pregnancy. It turned out that
twenty women of the first group and four women of the second group gave birth to premature
babies. Now, you submit your research paper to a scientific journal. The editors ask, “Are the
one hundred pregnant women in your study real or imaginary?” You answer, “I don’t know
whether they are real or imaginary. I don’t believe they are real. But I accept that they are real.
If we adopt the policy of using that assumption for the purpose of explanation, we can
understand why the twenty women had premature babies.” The editors will be perplexed by
your answer. They have two possible responses to you. One is kind; the other is unkind. Their
kind response is to let you know that science is an inquiry into the world, but that they
suspect that your manuscript is not an outcome of an inquiry into the world. Their unkind
response is to accuse you of having fabricated data, a serious violation of research ethics in
science. Of course, you did not fabricate the data, and the data are true. But the point is that if
you do not believe that they are true, you are opening yourself to the charge of the serious
misconduct, and to the charge that your understanding does not reflect the world. Belief plays
such a crucial role in science.
When scientists explain something in terms of a scientific theory, they believe that it is
real. For example, when they invoke Newtonian mechanics to explain why the Earth turns
around the Sun, they believe that the Earth turns around the Sun.
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If they do not believe that
something is real, they do not bother to explain it. It is for this reason that biologists do not
bother to explain why a unicorn has a horn, and that Ptolemaic astronomers did not bother to
explain why the Earth revolves around the Sun. If scientists explain something that they do
not believe to be real, they face a disconcerting question: “What is the point of explaining
something you do not believe to be real?” Thus, it is in part because scientists believe that
their explananda are real that their peers take their explanations seriously.
How about predictions? Suppose that you are a scientist and use Newtonian mechanics
to send a rocket to the Moon. You predict that the rocket will arrive on the Moon at a
particular time. Before you confirm the prediction, you may merely accept it. Once you
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Should they believe that Newtonian mechanics is true? Dellsén would say no, but I (2015: 226-228; 2016: 77-
78; 2017: 59-60) argue that problems arise when we explain something in terms of a scientific theory without
believing that it is (approximately) true. This paper, however, assumes for the sake of argument that Dellsén is
right, i.e., that it is legitimate merely to accept a scientific theory and then use it to explain phenomena.
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confirm it, however, you believe it. If you still merely accept it, you can be accused of
making no discrimination between confirmed and unconfirmed predictions, and more
importantly, your peers might dismiss your prediction, saying, “Why should I believe what
you don’t?” They may even suspect that you have fabricated data. Thus, it is in part because
scientists believe that their predictions are true that their peers take their predictions seriously.
To summarize, scientists believe at least that explained phenomena are real, and that
their confirmed predictions are true. In the absence of such beliefs, their peers might suspect
that their explanations and predictions do not concern the world, and that their understandings,
which allegedly arise from their explanations and predictions, do not reflect the world. Thus,
it is not acceptance but belief that is required for scientific understanding.
Let me now turn to Dellsén’s contention that understanding does not require
justification. The idea is that understanding results from explanations and predictions making
use of propositions, and that understanding can arise without any justification for the
propositions. He states this view as follows:
..there is no requirement in (U) that an agent has epistemic justification for the propositions on
which her understanding is based. More precisely, an agent may partially understand something
by virtue of grasping how to correctly explain or predict some aspect of it, even though she does
not have the epistemic justification required for knowing the propositions to which she appeals
in her explanations/predictions. (2016a: 76)
In order to illustrate this point, Dellsén (2016a: 76) offers the example of Einstein’s
explanation of Brownian motion in terms of the kinetic theory. He cites Einstein’s following
paragraph:
In this paper it will be shown that according to the molecular-kinetic theory of heat, bodies of
microscopically-visible size suspended in a liquid will perform movements of such magnitude
that they can be easily observed in a microscope, on account of the molecular motions of heat. It
is possible that the movements to be discussed here are identical with the so-called “Brownian
molecular motion”; however, the information available to me regarding the latter is so lacking in
precision, that I can form no judgment in the matter. (Einstein, 1905/1956: 1)
Einstein did not have enough information to determine whether the movements under
investigation were Brownian motion, so “the explanandum in Einstein’s explanation of
Brownian motion did not constitute knowledge for Einstein at the time” (Dellsén, 2016a: 76).
In addition, “the kinetic theory of heat was very much up for debate at the turn of the 20
th
century, with many physicists favoring alternative theories of heat that did not assume the
existence of submicroscopic molecules” (Dellsén, 2016a: 76). In short, Einstein was neither
justified in believing that the explanandum was true, nor justified in believing that the
explanans was true. Yet, he explained Brownian motion in terms of the kinetic theory, thereby
giving rise to the understanding of Brownian motion and making scientific progress.
Therefore, there can be an advance in scientific understanding and progress without
justification.
Does this episode spell doom for the epistemic approach? Epistemists would argue that
Einstein believed that a certain phenomenon existed although he was not sure whether it was
Brownian motion or not. He did not call the phenomenon Brownian motion because the name
‘Brownian motion’ was a theory-laden term presupposing the existence of microscopic
particles. Moreover, he made scientific progress simply because his insight into the
relationship between the kinetic theory and Brownian motion served as a means to establish