Identifying 'tribes' in India presents significant definitional challenges due to their immense heterogeneity and the fluid nature of social categories. There is no universally accepted definition, leading to ambiguities and debates.

Definitional Problems:

1. Heterogeneity: Indian tribes are not a monolithic group. They exhibit vast diversity in language, culture, economy, religion, and social organization. Applying a single definition to such a diverse population is inherently problematic.
2. Continuum vs. Discrete Categories: It's often difficult to draw a clear line between 'tribe' and 'caste' or 'peasant' groups. Many groups exist on a continuum, having undergone varying degrees of 'Hinduization' or assimilation into the mainstream, blurring the boundaries between tribal and non-tribal identities.
3. Colonial Legacy: The British administration categorized groups for administrative convenience, often based on 'primitive' characteristics, which might not accurately reflect their complex social realities or current status.
4. Lack of Consensus on Criteria: Various criteria have been used to define tribes (e.g., isolation, distinct culture, animism, primitive economy, common territory, endogamy). However, these criteria are often fluid, overlapping, and not uniformly applicable to all groups. For instance, many tribes are no longer isolated, and some have adopted elements of mainstream religions.
5. Self-identification vs. State-identification: There can be a discrepancy between how groups identify themselves and how the state categorizes them (e.g., as Scheduled Tribes). This can lead to political mobilization for inclusion or exclusion from the ST list, highlighting the social construction of 'tribal' identity.

Main Obstacles to Tribal Development in India: Despite constitutional safeguards and numerous development programs, tribal communities in India face formidable obstacles to their development:

1. Land Alienation: This is perhaps the most critical issue. Tribal lands are often alienated due to large-scale development projects (dams, mines, industries), forest policies that restrict traditional access, and encroachment by non-tribals. This leads to displacement, loss of livelihood, and cultural disruption.
2. Poverty and Indebtedness: Loss of land, limited access to modern economic opportunities, and exploitation by moneylenders and traders perpetuate cycles of poverty and indebtedness. Many tribals are forced into precarious labor conditions, sometimes leading to bonded labor.
3. Lack of Education and Health: Tribal areas often suffer from inadequate educational infrastructure, high dropout rates, and a curriculum that is not culturally sensitive. Similarly, healthcare facilities are scarce, leading to poor health outcomes, high infant mortality, and prevalence of diseases like malaria and malnutrition.
4. Exploitation and Discrimination: Tribals frequently face exploitation by middlemen, contractors, and even government officials. Social discrimination, rooted in historical prejudices, further marginalizes them and limits their access to public services and justice.
5. Cultural Erosion: Exposure to dominant cultures, forced assimilation, and the impact of modernization can lead to the erosion of traditional languages, customs, belief systems, and unique tribal identities, causing a sense of loss and alienation.
6. Ineffective Implementation of Policies: Despite progressive laws like the Panchayats (Extension to Scheduled Areas) Act (PESA), 1996, and the Forest Rights Act (FRA), 2006, their implementation is often weak due to bureaucratic apathy, corruption, lack of awareness, and resistance from vested interests.
7. Isolation and Lack of Infrastructure: Many tribal habitations are remote and lack basic infrastructure like roads, electricity, communication networks, and market access, hindering their integration into the mainstream economy and society.
8. Militancy and Conflict: In some regions, tribal grievances over land, resources, and identity are exploited by extremist groups, leading to armed conflicts that further disrupt development and displace communities.

Addressing these obstacles requires a multi-faceted approach that respects tribal autonomy, protects their land and resources, promotes culturally appropriate education and healthcare, and ensures effective implementation of protective legislation.