Med Health Care and Philos (2017) 20:373–381
Blurring nature at its boundaries. Vague phenomena in current
stem cell debate
Published online: 7 February 2017
© Springer Science+Business Media Dordrecht 2017
Notably, in contemporary philosophy there are no longer
doubts about the general relevance and context-sensitive
utility of vague phenomena. Thereby, vague phenomena
represent a vital challenge of its own kind insofar as they
take into account the irreducibility of the phenomenon of
life to certain physical processes.
Furthermore, they newly
illuminate the necessary relationship between words and
such objects to which those words refer assuming that
“both representational and nonrepresentational items can
have fuzzy boundaries” (Keil 2013, 151).
The present paper aims to pick up the thread of current
philosophical discussion both on vagueness or ambigu-
ity and on species concepts in order to extend it to genu-
ine bioethical issues. On that front, we take a fresh look
on ways how to evaluate two diﬀerent types of stem cells
whose juxtaposition can shed light on the ontological and
ethical status of a species and the process of its formation
(speciation): embryonic stem cells (ES) and induced pluri-
potent stem cells (iPS). This interdisciplinary study par-
ticularly focuses on the attempt to uncover hardly identiﬁ-
able conceptions of reality that require a certain concept of
vagueness having severe eﬀects on the deﬁnition of what a
species is. According to Keil (2013), in the current discus-
sion on vagueness we usually ﬁnd two fundamental con-
ceptions of reality serving as diﬀerent sources for diﬀerent
understandings of vagueness:
See for a contemporary rejection of mechanistic materialism draw-
ing on a Neo-Aristotelian life-form approach: Mulders (2016).
Vagueness in rebus or ontic vagueness does not need to be inco-
herent or unintelligible if we articulate it in spatial or mereologi-
cal terms. However, this cannot solve the problem of classiﬁcatory
vagueness, but it can help to understand why there must be a mutual
dependence between the vagueness of the word and the vagueness of
the object in order to describe living beings or life forms.
Abstract This paper illuminates the explanatory role of
vagueness und species membership against the background
of scientiﬁc developments in recent stem cell research.
With the help of the Neo-Aristotelian concept of “life form
naturalism” ontologically vague entities such as stem cells,
all above induced pluripotent stem cells (iPS), could be
described as necessary constituents for the correct sorting
and naming of natural processes and its bearers. Further-
more this speciﬁc assessment allows drawing some impor-
tant ontological and ethical consequences.
Keywords Vagueness · Species membership · Stem
cells · Life form · Constitutivism · Naturalism
Introduction: the ontological background
Although we live in times of highly specialized research
methods whose results are evidentially committed to exact-
ness, we consistently discover a signiﬁcant number of inde-
terminate and vague phenomena, ﬁrst and foremost in the
ﬁeld of stem cell research. Indeed, high-resolution elec-
tron microscopes give us useful insights into molecular
cell structures, but nevertheless we cannot explain exactly
whether and at what point we are allowed to refer to a via-
ble organism in the course of an embryonic development.
For this reason, we are rather forced to get along with clues
and presumed limits we have to approach to.
* Martin Hähnel
Chair of Bioethics, Catholic University Eichstaett-Ingolstadt,