Social capital

The notion of social capital expresses the idea that networks of relationships, in their multiple forms, have an intrinsic value that is beneficial for individual and collective action. Since the appearance of this concept in the academic field, studies on social capital have grown exponentially in different body of literature, thus constituting a vast and heterogeneous production. Although the positive effect of networks is a classic issue in social sciences—e.g., a subject already addressed by Tönnies' Gemeinschaft/Gesellschaft debate or in the Durkheimian concept of anomie—the conceptualization of social capital provided new vitality to the study of social relationships starting from the late 80's. In addition, the exponential growth of social capital analyses made this concept goes beyond the academic barriers, capturing the interest of the institutional discourse and the political agenda (Portes, 1998).

Origin of the concept
Three authors are considered the main contributors to the initial disclosure of the concept of social capital: Robert Putnam, James Coleman and Pierre Bourdieu. For Putnam (2000) social capital is an expression of societal virtues. Communities with fruitful webs of connections, Putnam (2000) argues, generate a "stock" of social resources that facilitate the societal coordination, and that can also help individuals to achieve their purposes. Similarly, for Coleman (1988) the relationships within a community have a specific function: they facilitate agents’ actions to accomplish goals and needs. Compared to these perspectives, Bourdieu's vision on social capital put major emphasis on this notion as individual good. The reason is that in Bourdieu (1986) social capital is linked to the possession of an enduring network of relationship that provide potential resources, such as information, influence, knowledge or social support. These resources represent thus a social capital that can be measured by looking the number of individual's connections, and also the volume of economic, cultural or symbolic capital possessed by each individual's ties (Bourdieu, 1986). Bourdieu's definition is what most is linked with Social Network Analysis (SNA) perspective (Wasserman and Faust, 2001).

Current issues
Many research areas on social capital have thus grown in the last three decades, such as labour market (Lin, 2001; Smith and Young, 2017) and family studies (Widmer, 2006), epidemiology (Valente, 2010), physical and mental health issues (Kawachi and Berkman, 2014; Ehsan et al., 2019). Theoretical and methodological advances have led to the conceptualization of different forms of bonding, bridging or linking social capital to understand the transmission of support (Rostila, 2011) or information (Granovetter, 1985) and how contacts link individuals to authorities (Szreter and Woolcock, 2004). SNA has contributed substantially to the conceptualization of these mechanisms (Burt, 2010), and it has now been considered a roadmap to strengthen links with the life course perspective (Alwin et al., 2018) and to extend inquiries on social capital to the digital world (Lu and Hampton, 2017). In addition, there is increasing emphasis among scholars on extending the analysis of what is called the 'dark side of social capital', and how networks can be a source of vulnerability through conflicts and barriers to resources (Everett and Borgatti, 2014).

References
Alwin, Duane F., Diane H. Felmlee, and Derek A. Kreager. 2018. Social Networks and the Life Course. Integrating the Development of Human Lives and Social Relational Networks. Basel: Springer International Publishing.
Bourdieu, Pierre. 1986. "The Forms of Capital." Pp. 241-58 in Handbook of Theory and Research for the Sociology of Education , edited by J. G. Richardson. New York:Greenwood.
Burt RS (2010) Neighbor Networks. Oxford: Oxford University Press.
Burt, Ronald S. 1992. Structural Holes: The Social Structure of Competition. Cambridge:Harvard Univesrity Press.
Coleman, James S. 1988. "Social Capital in the Creation of Human Capital." American Journal of Sociology 94:S95-120.
Ehsan, A., Klaas, H. S., Bastianen, A., & Spini, D. (2019). Social capital and health: A systematic review of systematic reviews. SSM-population health, 100425
Everett, M., & Borgatti, S. (2014). Networks containing negative ties. Social Networks, 38(1): 111–120. DOI: 10.1016/j.socnet.2014.03.005
Granovetter, Mark. 1985. "Economic Action and Social Structure: The Problem of Embeddedness." American Journal of Sociology, 91(3):481-510.
Lin, Nan. 2001. Social Capital: A Theory of Social Structure and Action. Cambridge: Cambridge university press.
Lu,W., & Hampton, K. N. (2017). Beyond the power of networks. New Media & Society, 19(6), 861–879. doi:10.1177/1461444815621514
Kawachi, I., & Berkman, L. F. (2014). Social capital, social cohesion, and health. Social Epidemiology, 2, 290–319.
Putnam, Robert D. 2000. Bowling Alone. The Collapse and Revival of AmericanCommunity. New York: Touchstone.
Rostila (2011). The facets of social capital J. Theory Soc. Behav., 41 (3) (2011), pp. 308- 326
Smith, S. S., & Young, K. A. (2017). Want, need, fit: The cultural logics of job-matching assistance. Work and Occupations, 44(2), 171–209.
Spini, Bernardi & Oris (2017) Vulnerability Across the LifeCourse. Research in Human Development, 14:1, 1-4, DOI: 10.1080/15427609.2016.1268891
Szreter, S. and Woolcock, M. 2004. “Health by Association? Social Capital, Social Theory, and the Political Economy of Public Health”, International Journal of Epidemiology 33(4): 650–667.
Wasserman, Stanley, and Katherine Faust. 1994. Social Network Analysis: Methods and Applications. New York: Cambridge University Press.
Widmer, ED (2006). Who are my family members? Bridging and binding social capital in family configurations. J. Soc. Pers. Relatsh. 23, 979–998.