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Science and God: An automatic opposition between ultimate explanations
, Nicholas Epley
Department of Psychology, University of Illinois at Urbana-Champaign, 603 E Daniel St. Champaign, IL 61820, USA
University of Chicago, 5807 South Woodlawn Avenue Chicago, IL 60637-1610, USA
Received 14 May 2008
Revised 8 July 2008
Available online 22 August 2008
Science and religion have come into conﬂict repeatedly throughout history, and one simple reason for
this is the two offer competing explanations for many of the same phenomena. We present evidence that
the conﬂict between these two concepts can occur automatically, such that increasing the perceived
value of one decreases the automatic evaluation of the other. In Experiment 1, scientiﬁc theories
described as poor explanations decreased automatic evaluations of science, but simultaneously increased
automatic evaluations of God. In Experiment 2, using God as an explanation increased automatic evalu-
ations of God, but decreased automatic evaluations of science. Religion and science both have the poten-
tial to be ultimate explanations, and these ﬁndings suggest that this competition for explanatory space
can create an automatic opposition in evaluations.
Ó2008 Elsevier Inc. All rights reserved.
Recent debates over intelligent design theory in science educa-
tion have brought long-standing conﬂicts between science and
religion back into public attention. On the surface, religion and sci-
ence may seem to be very different domains: science is directed to-
ward the understanding of physical systems, and religion is
concerned with more intangible spiritual and moral issues (Gould,
1999). Some scientists suggest that science and religion can be rec-
onciled as compatible belief systems (Collins, 2006). Others, mean-
while, are more skeptical and argue that the two ideologies are
inherently opposed, and that belief in one necessarily undermines
belief in the other (Dawkins, 2006; Zukav, 2001).
Although science and religion do not always conﬂict, a frequent
source of tension concerns the competition for explanatory space.
Religion and science offer different explanations for a wide array of
phenomena, including some of the most fundamental human is-
sues (e.g. intelligent design vs. natural selection). This direct oppo-
sition may cause the value of religion and science to become
inversely related when these explanations are brought into mind.
In the present research we investigate whether the evaluation of
science and religion may be automatically opposed, such that
increasing the perceived value of one as an explanatory system
diminished automatic positive evaluations of the other.
Explanation and belief
Causal explanations enable people to understand and predict
the world around them. Unexpected or unusual events automati-
cally prompt a search for causes (Weiner, 1985), and causal infer-
ences can be generated spontaneously with little effort by the
thinker (Hassin, Bargh, & Uleman, 2002). All explanations are not
created equal, however, and people prefer those that appear most
simple and coherent (Lombrozo, 2007). Explanations gain cogni-
tive support and psychological value as they appear to explain
more observations with fewer causes (Keil, 2006; Preston & Epley,
2005), especially those that explain diverse effects that are
branched far apart on a causal tree (Kim & Keil, 2003). In contrast,
alternate explanations for the same effects may possess a negative
association between them (Thagard, 2006), such that the perceived
validity of one can impact the perceived validity of the other (Slo-
man, 1994). Just as it is impossible to believe a single proposition
to be both true and false simultaneously (Gilbert, 1991), it may
be impossible to hold two competing explanations as both true
(or both false) simultaneously. As a result, the availability of one
plausible explanation may therefore diminish the perceived value
of another (Morris & Larrick, 1995).
As broad explanatory systems, religion and science each pro-
vide answers to a wide array of fundamental questions and con-
cerns, and so each have strong explanatory value. However,
these belief systems often provide different explanations for
the same phenomena, and this competition for explanatory
space can trigger conﬂict. Instances of this recurring conﬂict
can be found throughout history. Advances in scientiﬁc theories
that contradict religious explanations can threaten these beliefs
and are often met with resistance. Conversely, when scientiﬁc
explanations are poor, the value of religious explanations may
be enhanced. The central argument of intelligent design theory
is to point out gaps or failings in scientiﬁc explanations, thereby
enabling explanations based on other (generally divine) causes.
This is sometimes called the God of the Gaps argument (Lupfer,
0022-1031/$ - see front matter Ó2008 Elsevier Inc. All rights reserved.
* Corresponding author. Fax: +1 217 244 5876.
E-mail addresses: email@example.com,firstname.lastname@example.org (J. Preston).
Journal of Experimental Social Psychology 45 (2009) 238–241
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Tolliver, and Jackson (1996))—where science cannot explain, God
is invoked as a cause.
Compounding this conﬂict, both religion and science can be used
as ultimate explanations—primary causes that account for all events,
but rely on no further underlying mechanisms. Most modern day
religions depict God as the ‘‘unmoved First Mover” that is the ulti-
mate cause of everything but itself has no cause. Science theoreti-
cally promises a method for understanding all of one’s natural
observations, with the principal goal to uncover the mechanisms
that underlie all known phenomena. The search for the theory of
everything, a single equation that would be able to describe all as-
pects of matter and physics without appealing to any deeper explan-
atory base, has been dubbed the holy grail of physics (Barrow, 1992)
in a nod to the anticipated meaning that such an equation would pro-
vide. Conﬂict between science and religion over this prime explana-
tory space may create a negative association between the two, such
that the value of one may be inversely related to the automatic eval-
uations of the other. Enhancing the apparent explanatory power of
scientiﬁc explanations may automatically decrease positive evalua-
tions of religion, and vice versa. Likewise, apparent weakness in sci-
entiﬁc explanations may increase positive evaluations of religion,
and vice versa. This research investigated whether people’s auto-
matic evaluation of concepts related to science and religion would
indeed show evidence of such automatic opposition.
The present research
We manipulated, in two experiments, the perceived value of
either science or God as an ultimate explanation, and then mea-
sured automatic attitudes toward science and religion using a
semantic priming procedure with a categorization task. (Fazio &
Olson, 2003). Explicitly reported attitudes toward science and reli-
gion may be well-formed and resistant to change, but previous re-
search demonstrates that causal discounting does not require
explicit evaluation of alternatives and can occur outside of con-
scious awareness (Oppenheimer, 2004). Before one has the oppor-
tunity to consciously consider whether the two are logically
opposed or engage in effortful reconciliation we predicted that
automatic evaluations of science and religion would diverge
Experiment 1 investigated the use of scientiﬁc theories as ulti-
mate explanations. We were interested in questions of origin that
might be explained by a creator, speciﬁcally the origin of the uni-
verse and the origin of life on Earth. We predicted that better the-
ories would increase automatic positive evaluations of science,
whereas weaker theories would decrease these evaluations. More
important, we predicted that evaluations of God should be inver-
sely related to the explanatory power of these scientiﬁc theories.
Experiment 2 investigated whether manipulating the perceived va-
lue of a religious explanation would produce the opposite interac-
tion, increasing positive automatic evaluations related to religion
but decreasing those related to science.
Experiment 1: Scientiﬁc origins
One hundred twenty-nine six volunteers from The University of
Chicago, The University of Western Ontario, and Harvard University
agreed to participate in exchange for $5 or for partial course credit.
Participants were seated in a private lab room in front of a com-
puter. All instructions were given on the computer. Participants
read two passages that brieﬂy described the Big Bang Theory and
the Primordial Soup Hypothesis. In the Strong Explanation condi-
tion, each passage concluded with a statement that ‘‘this was the
best scientiﬁc theory on the subject to date, and does much to ac-
count for the known data and observations.” In the Weak Explana-
tion condition, each passage concluded with a statement that ‘‘this
was the best scientiﬁc theory on the subject to date, but it does not
account for the other data and observations very well, and raises
more questions than it answers.” Participants were asked, for each
passage, to choose the best title from two options.
Participants completed a semantic priming paradigm with a
categorization task (Fazio & Olson, 2003). Positive (e.g. ‘‘EXCEL-
LENT”) or negative (e.g. AWFUL) target words appeared on the
computer screen. Participants were asked to classify the words as
positive or negative as quickly as possible by pressing a computer
key. Each trial included a 250 ms premask (XXXXXX), a 15 ms pre-
sentation of a prime word (either ‘‘God” or ‘‘Science”, or a control
prime ‘‘Hat”/‘‘Window”), and a 50 ms post-mask (XXXXXX). After
the post-mask disappeared, the target word appeared and re-
mained until participants classiﬁed it as positive or negative. The
procedure included 120 randomly ordered trials: 20 for each prime
type and target value.
Reaction times were submitted to a 2 (Prime: God/Science) 2
(Target Valence: Positive/Negative) 2 (Explanatory Power of Sci-
ence: Weak/Strong) ANOVA with repeated measures on the ﬁrst
two variables. The predicted three-way interaction was signiﬁcant,
F(1,127) = 17.93, p< .001. We simpliﬁed this three-way interaction
by subtracting the mean reaction time to positive targets from
mean reaction time to negative targets for each speciﬁc prime
word to create an automatic attitude index toward Science vs.
God. Thus, greater numbers of this scale denote more positive eval-
uations of the targets (see Fig. 1). In the Strong Explanation condi-
tion automatic evaluations of science were more positive than
evaluations of God, F(1, 127) = 9.56, p< .001. The reverse relation-
ship was found in the Weak explanation condition, associations
with God were signiﬁcantly more positive than associations with
science, F(1,127) = 8.37, p< .001.
Fig. 1. Automatic evaluations of Science and God by explanatory power of Science,
J. Preston, N. Epley / Journal of Experimental Social Psychology 45 (2009) 238–241 239
Author's personal copy
Experiment 2: Divine origins
A similar automatic opposition between religious and scientiﬁc
beliefs should be observed by altering the perceived value of reli-
gious explanations (Preston & Epley, 2005). For example, a person
who actively uses religious explanations in daily life may not ﬁnd
science particularly useful. But, if one begins to feel doubt or loses
meaning for God, belief in science may be bolstered as a result.
Experiment 2 examined whether using God as an ultimate expla-
nations could create an automatic opposition between Science
Twenty-seven undergraduates from Harvard University volun-
teered to participate for partial course credit.
Participants were seated in a private laboratory room in front of
a computer. Participants in the explanation condition were in-
structed to: ‘‘list SIX things that you think God can explain.” Partic-
ipants in the control condition were given the instructions: ‘‘list
SIX things that you think can explain or inﬂuence God.” Existing re-
search demonstrates that this manipulation can inﬂuence the sub-
jective value of religious beliefs, with those using God to explain
other events reporting that religion is signiﬁcantly more meaning-
ful and important to them than those identifying events that could
explain God’s actions (Preston & Epley, 2005). All responses were
typed into the computer. Participants then completed the semantic
categorization task, as in Experiment 1.
Reaction times were submitted to a 2 (Prime: God/Science) 2
(Target word: Positive/Negative) 2 (Religious explanation:
Weak/Strong) ANOVA with repeated measures on the ﬁrst two fac-
tors. The predicted three-way interaction was signiﬁcant,
F(1,25) = 6.65, p< .02. Reaction times were converted into an auto-
matic attitude index as in Experiment 1 (see Fig. 2). In the control
condition, evaluations of God and Science did not differ signiﬁ-
cantly, F(1,25) = 1.32, ns. But when God was used as explanation,
automatic evaluations of God were more positive than evaluations
of Science, F(1,27) = 6.16, p< .05.
Religion and science offer inclusive systems of beliefs that help
to organize people’s understanding of the world they live in. When
these different beliefs compete with each other for explanatory
space, they also compete for their value. Here were report an auto-
matic opposition between evaluations of Science and God accord-
ing to their utility as ultimate explanations. In Experiment 1,
exposure to apparently poor scientiﬁc explanations for the origins
of the Universe and life on Earth enhanced positive automatic eval-
uations of God relative to Science, whereas apparently strong sci-
entiﬁc explanations resulted in more positive evaluations of
Science relative to God. In Experiment 2, a reciprocal relationship
was found when God was used as a strong explanation. When peo-
ple actively used God as an explanation for a variety of phenomena,
automatic evaluations of science were diminished as evaluations of
God were enhanced. These data suggest that using scientiﬁc theo-
ries as ultimate explanation can serve as an automatic threat to
religious beliefs, and vice versa. Perhaps more important, these
ﬁndings also indicate that explanatory weakness in one belief sys-
tem can bolster automatic evaluations of the other. These auto-
matic oppositions emerged despite making no explicit mention
of the potentially opposing belief system or to the possible conﬂict
between science and religion.
The implications of these ﬁndings are considerable, but some
questions remain. The ﬁrst concerns the mechanism underlying
of the automatic opposition: whether these results stem from an
automatic causal discounting as we have suggested, or reﬂect an
awareness of the opposition publicized in the popular culture. If
these effects do represent an explanatory opposition, then they
should only arise where the alternative belief system seems appro-
priate. For example, scientiﬁc explanations of more mundane top-
ics (e.g. photosynthesis) would not be expected to impact
evaluations of God, where religious explanations do not apply. If
these results represent a cultural knowledge of opposition, then
we may not see these effects at all in societies where religion
and science are viewed as compatible. In either case, there are sig-
niﬁcant implications of these ﬁndings. A second question concerns
the interplay between automatic opposition and explicit attitudes.
We expect this relationship to be complex, and impacted by many
other social factors like religious background, education, and cul-
ture. Attitudes toward science and religion are often deeply held
convictions and so may be resistant to change to by brief exposure
to explanatory information. However, continued use of one system
as ultimate explanation over time may result in an opposition of
these explicit beliefs as well. Indeed, whereas 85–95% of the gen-
eral US population reliably report belief in God (Gallup, 2005), this
is only 40% among those with a B.Sc., and only 7% among members
of the National Academy of Science (Larson & Witham, 1998).
Automatic attitudes and evaluations of the kind we have demon-
strated often serve as initial ‘‘gut” reactions that guide subsequent
cognitive processing, and may be reﬂected in an experience of
threat if one’s explicitly preferred explanatory system is called into
question. Such threat experiences may activate subsequent moti-
vated reasoning to defend one’s belief system among strong believ-
ers (Haidt, 2002), but may sow the initial seeds of doubt among
weaker believers. How the automatic opposition impacts explicit
beliefs, or how explicit beliefs impact the consequences of the
automatic associations we have documented, is an important ques-
tion for further research.
This is not to suggest that science and religion must always con-
ﬂict, nor that one system of belief must necessarily be chosen over
the other. But it may be that such reconciliations are only possible
following mental effort exerted to overcome this initial opposition.
How the automatic opposition impacts explicit beliefs, or how ex-
Fig. 2. Automatic evaluations of Science and God by explanatory power of God,
240 J. Preston, N. Epley / Journal of Experimental Social Psychology 45 (2009) 238–241
Author's personal copy
plicit beliefs impact the consequences of the automatic associa-
tions we have documented, is an important question for further re-
search. In any case, conﬂict between science and religion is not an
issue that is likely to go away any time soon. These experiments
suggest is that the frequent competition between science and reli-
gion as ultimate explanations is likely to create an intuitive and
automatic opposition that may present a permanent challenge
for both systems of belief.
We thank the Social Sciences and Humanities Research Council
of Canada and the National Science Foundation for ﬁnancial sup-
port; Leanne Gaffney, Belinda Hammound, Megan Kolasinski, Jas-
mine Kwong, Christine Mathieson, Aram Seo for assistance with
data collection; and Bertram Gawronski, Melissa Ferguson, Justin
Kruger, Tania Lombrozo, Ara Norenzayan, and James Olson for
comments on a previous version of this manuscript.
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