Facts and doubts on the beginning of human life - scientific, legal, philosophical and religious controversies.

It is very complicated to give correct answer to the question "How to define human life?" Nowadays dilemmas consider the respect of human life from the birth to death involve not just biology but also other sciences like philosophy, theology, sociology, psychology, law and politics. These sciences evaluate the topic from different points of view. Integration of all of these perspectives could result with a proper definition. The principal purpose of this paper is to try to determine when a human individual begins. If this proves to be too difficult, we might have to settle for a specific stage in the reproductive process before which it would be impossible to say with any plausibility that a human individual exists. It is necessary to return the moral dimension of observation to the science of life. The point is to reconcile the universal ethical principles concerning the absolute value of life with the everyday challenges and dilemmas. It is our deepest conviction that life has an absolute value and that there always remains something indestructible and substantial in life, which may neither be evaluated by anything final, nor completely reduced to the material biological equivalent and the genetic substratum.

The theoretical foundations of enaction: Precariousness.

Enaction is an increasingly influential approach to cognition that grew out of Maturana and Varela's earlier work on autopoiesis and the biology of cognition. As with any relatively new scientific discipline, the enactive approach would benefit greatly from a careful analysis of its theoretical foundations. Here we initiate such an analysis for one of the core concepts of enaction, precariousness. Specifically, we consider three types of fragility: systemic, processual and thermodynamic. Using a glider in the Game of Life as a toy model, we illustrate each of these fragilities and examine the relationships between them. We also argue that each type of fragility is characterized by which aspects of a system are hardwired into its definition from the outset and which aspects are emergent and hence vulnerable to disintegration without ongoing maintenance.

Earth's oldest land ecosystem spotted in drilled cores.

Campaign probes for earliest signs of oxygen-producing life.

Reductionism, Vitalism, and Holism.

The reductionist strategy, adopted by physics and chemistry, which was based on the effort to reduce the concepts necessary for the statement of scientific explanations to a minimum, was attractive to those who worked in the biomedical field. On the other hand, the vitalistic point of view opposed mechanism, believing that there were processes in living organisms that do not obey the laws of physics and chemistry. Finally, the holistic approach is focused on the evidence that the organized whole is almost always much more than the sum of its parts, and have led to direct attention to emerging qualities in a highly organized system which is a living being.

What is life?

BACKGROUND: Many traditional biological concepts continue to be debated by biologists, scientists and philosophers of science. The specific objective of this brief reflection is to offer an alternative vision to the definition of life taking as a starting point the traits common to all living beings. RESULTS AND CONCLUSIONS: Thus, I define life as a process that takes place in highly organized organic structures and is characterized by being preprogrammed, interactive, adaptative and evolutionary. If life is the process, living beings are the system in which this process takes place. I also wonder whether viruses can be considered living things or not. Taking as a starting point my definition of life and, of course, on what others have thought about it, I am in favor of considering viruses as living beings. I base this conclusion on the fact that viruses satisfy all the vital characteristics common to all living things and on the role they have played in the evolution of species. Finally, I argue that if there were life elsewhere in the universe, it would be very similar to what we know on this planet because the laws of physics and the composition of matter are universal and because of the principle of the inexorability of life.

Untangling the Animacy Organization of Occipitotemporal Cortex.

Some of the most impressive functional specializations in the human brain are found in the occipitotemporal cortex (OTC), where several areas exhibit selectivity for a small number of visual categories, such as faces and bodies, and spatially cluster based on stimulus animacy. Previous studies suggest this animacy organization reflects the representation of an intuitive taxonomic hierarchy, distinct from the presence of face- and body-selective areas in OTC. Using human functional magnetic resonance imaging, we investigated the independent contribution of these two factors-the face-body division and taxonomic hierarchy-in accounting for the animacy organization of OTC and whether they might also be reflected in the architecture of several deep neural networks that have not been explicitly trained to differentiate taxonomic relations. We found that graded visual selectivity, based on animal resemblance to human faces and bodies, masquerades as an apparent animacy continuum, which suggests that taxonomy is not a separate factor underlying the organization of the ventral visual pathway.SIGNIFICANCE STATEMENT Portions of the visual cortex are specialized to determine whether types of objects are animate in the sense of being capable of self-movement. Two factors have been proposed as accounting for this animacy organization: representations of faces and bodies and an intuitive taxonomic continuum of humans and animals. We performed an experiment to assess the independent contribution of both of these factors. We found that graded visual representations, based on animal resemblance to human faces and bodies, masquerade as an apparent animacy continuum, suggesting that taxonomy is not a separate factor underlying the organization of areas in the visual cortex.

Life's organization between matter and form: Neo-Aristotelian approaches and biosemiotics.

In this paper, I discuss the neo-Aristotelian approaches, which usually reinterpret Aristotle's ideas on form and/or borrow the notion of formal cause without engaging with the broader implications of Aristotle's metaphysics. In opposition to these approaches, I claim that biosemiotics can propose an alternative view on life's form. Specifically, I examine the proposals to replace the formal cause with gene-centrism, functionalism, and structuralism. After critically addressing these approaches, I discuss the problems of reconciling Aristotelianism with the modern view of life's organization. I claim that the notion of the final cause proposes a cosmological hierarchy and that this is the main problem with applying the formal cause to biology. An alternative categorization of conceptualizing life's form involves (1) the processual identity, (2) relational property clusters, and (3) context-dependent transmission of representational units. The third category points to a semiotic basis of the form of life. In this context, I offer to readjust the focus of the problem of matter-form duality by pointing out that form is primarily an issue of the subject-object relation. Biosemiotics helps to understand the constructive role of symbolic representation in living systems, which is crucial to extend the analysis of the form from cognitive representations to external phenomena. Emergence of subjectivity and perspectivity of interactions are key elements to bridge the form and actual processes within a non-hylomorphic account. To demonstrate transitions from the physical influence of shapes to the organic recognition of forms, I address the biological studies on the synchronization of coincidental inputs and enzyme specificity.

The enigma of life: confronting marvels at the edges of science.

Einstein famously claimed that "the most incomprehensible thing about the universe is that it is comprehensible." This statement suggests that no amount of scientific explanation will suffice to make sense of the bizarre situation of the human mind within the universe. So what are the actual roles of awe and wonder within the framework of contemporary science? How, for instance, do awe and wonder inform scientists' understanding of the phenomena they are researching? What aspects of contemporary science are more likely to elicit wonder, and why? Is science rechanneling our innate thirst for knowledge and understanding toward more concrete and palpable realities, or is it aggravating the tension between truth and meaning by revealing the scope of our ignorance when it comes to probing the ultimate nature of reality? Physicist Marcelo Gleiser, experimental psychologist Tania Lombrozo, and physician Gavin Francis analyze the impact of awe and wonder on their own work and on the mindsets of their colleagues carrying out leading-edge scientific research.

When is search for meaning in life beneficial for well-being? A cross-national study.

Previous research has found cross-national variations in the association between search for meaning in life (SMIL) and well-being (i.e. SMIL-WB link). This study extended and tested a "self-improvement hypothesis" that accounts for such cross-national variations based on an international database-the sixth wave of World Values Survey. SMIL represents a self-improvement effort which is more demanded in contexts with stronger external constraints. Thus, we expected a stronger positive SMIL-WB link in such contexts. A series of multilevel analyses was used to verify this hypothesis. The results showed that the SMIL-WB link varied across different societies, with well-being indexed by happiness, life satisfaction and subjective health. Moreover, external constraints from cultural, social-institutional, economic and ecological contexts (collectivism, peace threats, economic scarcity and environmental threats) moderated the SMIL-WB links. We thus call for advancing SMIL theory by considering person-context interaction.

Global human-made mass exceeds all living biomass.

Humanity has become a dominant force in shaping the face of Earth1-9. An emerging question is how the overall material output of human activities compares to the overall natural biomass. Here we quantify the human-made mass, referred to as 'anthropogenic mass', and compare it to the overall living biomass on Earth, which currently equals approximately 1.1 teratonnes10,11. We find that Earth is exactly at the crossover point; in the year 2020 (± 6), the anthropogenic mass, which has recently doubled roughly every 20 years, will surpass all global living biomass. On average, for each person on the globe, anthropogenic mass equal to more than his or her bodyweight is produced every week. This quantification of the human enterprise gives a mass-based quantitative and symbolic characterization of the human-induced epoch of the Anthropocene.