Invisible Hand and Wealth Redistribution

If there were, as Smith supposes, inherent in Economic activity, a tendency towards equilibrium, its scope would be general, not localized, i. e. not merely specific to Supply-Demand contexts.  Rather, it would also correct widespread imbalances, such as disparities in wealth.  Accordingly, the redistribution of wealth could be interpreted as a manifestation of such a general tendency.  Thus, for example, taxation that funds government benefits to the needy could be appreciated as an expression of Smith's Invisible Hand, not as in conflict with it, contrary to the protests of many contemporary Capitalists.

Profit and Pleasure

The modeling of Utilitarianism on Smith's system is based on the correlations of Pleasure with Profit, and Pain with Loss.  Now, the latter of each pair connotes a net quantity, i. e. an increase or decrease with respect to a prior condition.  But, beginning with Locke, a sense-datum, such as Pleasure or Pain, is a presupposition-less event.  Therefore, because Utilitarianism is an Empiricist doctrine, Bentham's and Mill's attempts to apply Empiricism to Smith's system are structurally flawed, at minimum. 

Invisible Hand, Individual, Collective

In the contemporary popular imagination, the Invisible Hand is a principle governed by an Individualistic ethos, insofar as income is conceived as reflecting the worthiness of its recipient.  However, as, as Smith conceives it, its primary role is to achieve equilibrium between Supply and Demand, it is independent of the conflicting self-interests that require resolution in order for an exchange to take place.  In other words, income is an expression of the subordination of the interests of the involved parties to compromise.  Thus, according to Smith, the principle is governed by the well-being of the collective, which requires the smooth interactions that it facilitates, contrary to the presumption of contemporary Capitalists.

Invisible Hand, Self-Interest, Hate

In Smith's Economic system, the Invisible Hand functions as a corrective to self-interested motives.  Hence, it is possible that he conceives it as a substitute for Sympathy, which serves the same role in his earlier work.  But, if, so, he now leaves unmodified other expressions of selfishness, e. g. emotions, such as hate.

Greatest Happiness and Optimal Happiness

The complete satisfaction of each of one's wishes can be called one's 'greatest happiness'.  Likewise, the achievement of the greatest happiness of each party can be called the 'total' greatest happiness.  Thus, the total greatest happiness entails the compossibility of each of the individual greatest happinesses.  However, as the Law of Supply and Demand reflects, that compossibility cannot be presumed to obtain, therefore, requiring compromise, typically via negotiation, the optimal result of which is the point of equilibrium.  So, the best-case scenario under such conditions, for either individual party or collective, can be called the 'optimal' happiness, which is likely what Mill intends by the formulation 'greatest happiness for the greatest number', if the standard application of the Utilitarian Calculus is any indication.  Now, Utilitarianism vacillates between description and prescription, i. e. between a characterization of how people actually conduct themselves, and a formula for determining the best course of action.  But, the problem with the latter is that, as has been previously discussed, there can be a discrepancy between real equilibrium and apparent equilibrium, with the latter the product of expressed terms, rather than of what is privately willed, and, hence, the product of guesswork.  In other words, the utility of the Utilitarian Calculus is itself limited by the unavailability of requisite knowledge, i. e. the real will of others.

Supply, Demand, Conflicting Interests

According to the Egoist Psychology to which Capitalists subscribe, the fundamental elements of the situation to which the 'Law of Supply and Demand' is usually applied are inherently conflicting interests--the seeking of each party to maximize gain and minimize costs, the achievement of which can come only at the expense of the other.  Thus, in a simple sale, the ideal for the buyer is to pay nothing, while that for the seller is to receive an infinitely large amount.  Of course, in practice, each party typically enters into a negotiation with a specific limit in mind--the maximum that the buyer is willing to spend, and the minimum that the seller is willing to receive. Accordingly, the equilibrium point is halfway between those two amounts.  However, in usual actuality, neither side is aware of the limit of the other, so, the terms of the ensuing negotiating may bear little resemblance to the privately willed ones, with the result an equilibrium that likewise bears little resemblance to the potential of the situation.  So, any assumption that the 'Law' is functioning in the service of achievement of optimal results is groundless.

Supply-Side Interests

In any Economic exchange, each party has a supply and a demand, with money often one of each.  Thus, the term 'Supply-Side' does not, in itself, distinguish one party from another.  Likewise, the term 'Supply-Side Economics' is, in itself, trivial.  Rather, what it typically denotes is the interests of the owners of the means of production, as opposed to those of consumers, and to the needs of those too poor to enter into any exchange.  Accordingly, for example, where that system prevails, profitability justifies the production and sale of junk, rather than that of useful or of vital goods.