For New Readers of Adam Smith's Moral Sentiments and Wealth Of Nations
A correspondent posted a comment and the gist of it is discussed below:*
New readers of Adam Smith’s Works will understood them better by thinking of the context in which he wrote them. Briefly, he published two major Works, Moral Sentiments (1759) and Wealth Of Nations (1776), both running to several editions before he died in 1790.
Moral Sentiments (TMS) was largely based on his lectures in Moral Philosophy delivered to undergraduates at Glasgow University from 1751-64. Smith was educated in moral philosophy by Francis Hutcheson, the Professor of Moral Philosophy from 1737-40 and we can assume he largely followed Hutcheson’s syllabus, though he did not always represent Hutcheson’s views.
TMS represents Smith’s own views as they developed after leaving Glasgow and attended Balliol College, Oxford (1740-46), the latter largely by private self-reading as Oxford Professors had “given up even the pretence of teaching”. His private reading included David Hume’s “Treatise” for which he was chastised by his tutors who caught him reading it in his College room.
TMS placed his chapter overview of the history of Moral Sentiments in Classical times (Greece and Rome) and how the subject developed through to the 18th century at the end of the book (Part 7). He starts TMS by going straight into the subject of moral sentiments (Parts 1-6), which may be heavy going for beginners who do not have access to a tutor who would (should) explain his ideas as they read through the book.
May I suggest that you read my explanations of TMS in “Adam Smith: a moral philosopher and his political economy”, 2nd paperback edition 2008, Palgrave-Macmillan (paperback which is also much cheaper than the 1st edition). This may help you while reading TMS. There are many other good aids to reading TMS. I had the same problem when I read TMS right through for the first time (I was flying home to Scotland from North America on an overnight flight. It was some time later after a couple more reads through and after reading several other sources too, before I ‘got it’.
Basically, Smith writes about humans as social beings, learning how to behave (in the ‘great school of self-command’, starting in the school-yard) from those they live with or near (because other people in society act as a “mirror” on their conduct, which moulds to some extent their behaviours, their moral conduct and their sentiments). Morality is not innate, nor derived from revealed religion. Smith’s device was that of an “impartial spectator” that judges one’s conduct. Society’s laws also influence, and among most people also constrain their behaviour.
This is where later editions, especially the sixth, 1789, Smith reduced the number of his references to theological language, especially after his mother died in 1784. He became more secular without anchoring TMS in revealed religion (as in the 1st and early editions).
Wealth Of Nations reproduces verbatim sections from his “Lectures in Jurisprudence’  from students’ notes, and places this title in its historical context. WN was not a textbook on economics; it is a critique on the prevailing mercantile political economy of Britain in its historical context and should be read as such. Its economics is fairly basic by Econ 102 standards.
Most modern economists have not read WN and those few that try often give up because modern economics is taught without any historical context, or indeed any prevailing connection to how economies developed to get where they are today. Modern economic theories are divorced from the real world, as they must be if they represent them in largely two dimensional maths, roughly where ‘hard’ science was in the 1870s. Even attempts to found a theory of “general equilibrium” mathematically are so far divorced from the real world as to be of little value in practice, as in the Welfare theorem which may produce a society that is perfectly disgusting by most moral standards.
Two or more carbon atoms behave the same on Earth as they do anywhere else in the Universe, but two or more humans might behave differently across the same street, or within the same family. Hence treating humans as if they behave the same or even behave predictably across time and space is likely to disappoint those who postulate the same rational behaviour for them all. That is why Smith said nothing about humans as subject to the postulate of common rationality: Homo economicus is a fable agreed upon by those blind to the world and history of humans around them.
Smith said humans have the power of reasoning, which is not the same as sharing a common universal Rationality. Self-interest is far more complex than rationality. Moreover humans can only achieve their self-interests in co-operation with other self-interested humans. In the course of seeking co-operation, the self-interests of individuals are mediated by what is acceptable to both of them and that process requires mutual persuasion – or, unhappily, in its absence it invites degrees of coercion (tyranny, strikes, wars). The meaning of all self-interested inter-actions by real people within the context of moral sentiments is elaborated by Smith throughout TMS and illustrated in WN.
* [I hope this clarifies your question from (apologies) what I remember of it. I passed your comment for publishing and moved on to something else. Later when I looked for your comment I could not find it and it wasn’t where I thought it was.]