The concept of "maximum social gain" in public policy making is indeed an attractive and noble goal. It suggests that policies should be designed to maximize the overall welfare, utility, or benefit for society as a whole, often implying an optimal allocation of resources and a distribution of benefits that leads to the greatest good for the greatest number. Rooted in utilitarian philosophy, this objective appeals to our sense of rationality, efficiency, and collective well-being.

Attractiveness of the Goal:

1. Ethical Appeal: It aligns with the intuitive idea that government should strive to improve the lives of its citizens and enhance collective welfare.
2. Rationality and Efficiency: It implies a systematic, evidence-based approach to policy-making, where costs and benefits are carefully weighed to achieve the most efficient and beneficial outcomes for society.
3. Public Interest: It positions policy-making as a pursuit of the overarching public interest, transcending narrow individual or group interests.

Why it is Rarely Found in Practice (Challenges): Despite its attractiveness, achieving "maximum social gain" in practice is exceedingly difficult, if not impossible, due to a multitude of inherent complexities and constraints:

1. Defining and Measuring "Social Gain": The most fundamental challenge is defining what constitutes "social gain" and how to measure it. Society's welfare is not a monolithic, easily quantifiable entity. It encompasses diverse and often incommensurable values such as economic prosperity, environmental quality, social justice, individual liberty, cultural preservation, and public health. How does one aggregate these disparate values into a single metric of 'gain'? For example, how do you compare the economic benefits of a new factory with its environmental costs or the social impact on a displaced community?
2. Value Pluralism and Conflicting Interests: Society is not a homogenous entity with shared preferences. Different groups, communities, and individuals have diverse, often conflicting, values, interests, and priorities. A policy that brings significant 'gain' to one segment of society might impose substantial 'loss' on another. Maximizing gain for the majority might mean marginalizing or harming a minority, raising serious ethical questions about equity and justice.
3. Distributional Effects: Even if an overall 'net gain' could be calculated, policies inevitably create winners and losers. The distribution of these gains and losses is a critical political and ethical consideration. A policy might maximize aggregate social gain but lead to highly unequal or unjust outcomes, which may not be acceptable to society.
4. Information Asymmetry and Bounded Rationality: Policy-makers rarely possess perfect information about all possible alternatives, their consequences, or the preferences of all citizens. They operate under conditions of bounded rationality, meaning their cognitive capacity to process vast amounts of information and predict all outcomes is limited. This makes true optimization for maximum gain practically unachievable.
5. Political Constraints and Power Dynamics: Policy-making is inherently a political process, not a purely rational one. Decisions are influenced by lobbying, electoral cycles, interest group pressures, bureaucratic politics, and the need for compromise and coalition-building. Policies are often the result of bargaining and negotiation, aiming for political feasibility and consensus rather than pure social optimization.
6. Unintended Consequences: Policies often have unforeseen and unintended consequences that can negate or diminish the expected social gain. The complexity of social systems makes it difficult to predict all direct and indirect effects of an intervention.
7. Measurement Difficulties: Quantifying many social benefits (e.g., improved quality of life, happiness, civic engagement) is notoriously difficult and often subjective, making a precise calculation of 'maximum gain' elusive.
8. Short-term vs. Long-term Trade-offs: Policies may offer immediate benefits but incur long-term costs, or vice-versa. Balancing these temporal trade-offs adds another layer of complexity.

In conclusion, while "maximum social gain" serves as an attractive normative ideal, guiding policy-makers to consider broader societal welfare, its full realization in practice remains an elusive goal. The inherent complexities of defining and measuring 'gain,' navigating value pluralism, addressing distributional concerns, and operating within political and informational constraints mean that policy-making often involves satisficing (finding a 'good enough' solution), incremental adjustments, and balancing competing interests, rather than achieving a singular, universally agreed-upon maximum social gain.