Ma`rifat Falsafi, Volume 23, Issue 2, No 90, Year 2026 , Pages 113-137
The Challenge of the Tautological Definition of "Fitness" from the Perspective of the Explanatory Power of "Natural Selection" in Evolutionary Theory and a Critical Review of Elliott Sober's Response
Article Type:
Research
Writers:
✍️ Masuod Toossi Saeidi
/ Assistant Professor of Institute for Science and Technology Studies, Shahid Beheshti University, Tehran, Iran. / m_tousi@sbu.ac.ir
/ Assistant Professor of Institute for Science and Technology Studies, Shahid Beheshti University, Tehran, Iran. / m_tousi@sbu.ac.irAbstract:
This paper examines the circularity challenge inherent in the definition of “fitness” from the standpoint of the explanatory value of natural selection in evolutionary theory. The fundamental issue arises from the fact that fitness is often defined in a circular manner without offering an independent criterion. In other words, employing the statement “those that survive are the fitted ones” without specifying the precise causal factors for survival transforms natural selection into a tautology: “those that survive are the ones who survive.” Initially, the paper reviews the historical background and the conceptual position of fitness in Darwin’s work, regarding the efforts of earlier biologists in formulating evolutionary theory. It then thoroughly examines the criticisms raised by philosophers and biologists such as Popper and Brandon. Subsequent sections analyze Elliott Sober’s response to this tautology challenge, in which he proposes a probabilistic propensity interpretation of fitness—incorporating viability and fertility components—to establish a causal formulation. However, the analysis reveals that even Sober’s proposal regarding the causal role of variety in fitness within evolution faces significant challenges, ultimately leaving his response inconclusive.
چکیده و کلیدواژه فارسی (Persian)
Title :چالش این همانگویی تعریف «سازگاری» از منظر ارزش تبیینی «انتخاب طبیعی» در نظریه «تکامل» و بررسی انتقادی پاسخ الیوت سوبر به آن
Abstract:
این مقاله به بررسی چالش اینهمانگویی در تعریف «سازگاری» از منظر ارزش تبیینی انتخاب طبیعی در نظریة «تکامل» میپردازد. مسئلة اصلی از آنجا ناشی میشود که تعریف «سازگاری» غالباً بهصورت دوری و بدون ارائة معیار مستقل، به بقا و تولیدمثل موجود زنده ارجاع میدهد. بهعبارت دیگر، کاربرد گزارة «آنهایی که زنده میمانند، سازگارترند» بدون تبیین دقیق علت بقا، موجب میشود انتخاب طبیعی به یک اینهمانگویی تقلیل یابد: «آنهایی که زنده میمانند، همانهایی هستند که زنده میمانند». مقاله ابتدا پیشینة تاریخی و جایگاه مفهومی «سازگاری» را نزد داروین با تأکید بر تلاشهای زیستشناسان پیش از او در صورتبندی نظریة «تکامل» مرور کرده، سپس نقدهایی را که از سوی فیلسوفان و زیستشناسانی همچون پوپر و براندون دربارة اینهمانگویی انتخاب طبیعی مطرح شدهاند، بهتفصیل بررسی نموده است. در ادامه، تحلیل انتقادی پاسخ الیوت سوبر به این چالش ارائه شده؛ جایی که سوبر با پیشنهاد تعریف «سازگاری» بهعنوان گرایشی احتمالاتی (شامل مؤلفههای زندهمانی و باروری)، در پی صورتبندی علّی این اصطلاح است. با این حال، تحلیلهای ارائهشده نشان میدهند که حتی پیشنهاد سوبر مبنیبر نقش علّی «تنوع در سازگاری» در فرایند تکامل، با چالشهای مهمی ـ ازجمله چالش اینهمانگویی ـ مواجه است و ازاینرو پاسخ او نیز هنوز نهایی تلقی نمیشود.
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Toossi Saeidi, Masuod. (2026) The Challenge of the Tautological Definition of "Fitness" from the Perspective of the Explanatory Power of "Natural Selection" in Evolutionary Theory and a Critical Review of Elliott Sober's Response. Ma`rifat Falsafi, 23(2), 113-137 https://doi.org/10.22034/marefatfalsafi.2025.5002165.
Masuod Toossi Saeidi."The Challenge of the Tautological Definition of "Fitness" from the Perspective of the Explanatory Power of "Natural Selection" in Evolutionary Theory and a Critical Review of Elliott Sober's Response". Ma`rifat Falsafi, 23, 2, 2026, 113-137
Toossi Saeidi, M.(2026) 'The Challenge of the Tautological Definition of "Fitness" from the Perspective of the Explanatory Power of "Natural Selection" in Evolutionary Theory and a Critical Review of Elliott Sober's Response', Ma`rifat Falsafi, 23(2), pp. 113-137
