The investment portfolio is not a values statement. This is a distinction that a significant and growing number of investors resist, for understandable psychological reasons—the companies one owns represent, in some sense, the economic activities one is financing, and it is natural to prefer that those activities align with one's values. But the conflation of investment decisions with value expression produces predictable and avoidable investment errors, and understanding the distinction between investing in what one believes in and investing in what is likely to produce an adequate return is essential to managing the former without sacrificing the latter.
The most direct form of values-driven investment error is the assumption that businesses engaged in activities one considers admirable are better investments than businesses engaged in activities one considers neutral or objectionable. This assumption has no logical foundation. The financial returns of a business are determined by its economics—its revenue growth, its margin structure, its capital efficiency, the durability of its competitive advantages—not by the social or environmental merit of its activities. A renewable energy company with poor unit economics is not a good investment because clean energy is admirable. A firearms manufacturer with excellent capital efficiency and durable competitive advantages is not a bad investment because firearms are objectionable to some investors. The values and the economics are independent variables.
The practical consequence of values-driven investment selection is a systematic bias in the investment universe that is likely to impair returns without providing proportional benefit to the causes the investor cares about. The investor who excludes entire sectors from her consideration set on the basis of values is reducing competition in the excluded sectors—potentially making their valuations more attractive for the investors who have no such exclusions—while concentrating her own portfolio in included sectors that may be fully priced precisely because they attract the attention of other values-driven investors. This is not a theoretical concern; the empirical literature on values-screened investment strategies suggests that exclusions tend to reduce diversification and risk-adjusted returns without demonstrably improving social outcomes.
This does not mean that values should have no role in financial decision-making. It means that the role they should play is different from the one most values-driven investors assign them. Values appropriately govern the minimum acceptable standard for investments one is willing to make—screening out companies engaged in outright fraud, or sectors one considers categorically unacceptable—not the positive selection criteria that determine what to buy. Within the set of acceptable investments, the selection criteria should be financial: value, quality, competitive position, management integrity. The values provide the boundary conditions; the financial analysis does the work of selection within those conditions.
The investor who separates these functions clearly—who applies values as a screen and financial analysis as a selector—is in a fundamentally sounder position than the one who allows values to substitute for financial analysis. She is not abandoning her values in her investment decisions; she is recognising that her investment portfolio is not the most effective instrument for expressing them, and that the financial returns she generates can, if she chooses, be directed toward causes she cares about far more efficiently than the indirect mechanism of values-screened investing.