[Footnote 1:  I use the expressions ‘moral sanction’ and ’moral sentiment’ as equivalent terms, because the pleasures and pains, which constitute the moral sanction, are inseparable, even in thought, from the moral feeling.  The moral feeling of self-approbation or self-disapprobation cannot even be conceived apart from the pleasures or pains which are attendant on it, and by means of which it reveals itself to us.

It should be noticed that the expression ‘moral sentiment’ is habitually used in two senses, as the equivalent (1) of the moral feeling only, (2) of the entire moral process, which, as we shall see in the third chapter, consists partly of a judgment, partly of a feeling.  It is in the latter sense, for instance, that we speak of the ’current moral sentiment’ of any given age or country, meaning the opinions then or there prevalent on moral questions, reinforced by the feeling of approbation or disapprobation.  As, however, the moral feeling always follows immediately and necessarily on the moral judgment, whenever that judgment pronounces decisively for or against an action, and always implies a previous judgment (I am here again obliged to anticipate the discussion in chapter 3), the ambiguity is of no practical importance at the present stage of our enquiry.  It is almost needless to add that the word ‘sentiment,’ when used alone, has the double meaning of a feeling and an opinion, an ambiguity which is sometimes not without practical inconvenience.]

The terms ‘conscience’ and ‘moral sense’ are very convenient expressions for popular use, provided we always bear in mind that ‘illuminate’ or ‘instruct’ your ‘conscience’ or ‘moral sense’ is quite as essential a rule as ‘follow’ your ‘conscience’ or ‘moral sense.’  But the scientific moralist, in attempting to analyse the springs of moral action and to detect the ultimate sanctions of conduct, would do well to avoid these terms altogether.  The analysis of moral as well as of intellectual acts is often only obscured by our introducing the conception of ‘faculties,’ and, in the present instance, it is far better to confine ourselves to the expressions ‘acts’ of ‘approbation or disapprobation,’ ’satisfaction or dissatisfaction,’ which we shall hereafter attempt to analyse, than to feign, or at least assume, certain ‘faculties’ or ‘senses’ as distinct entities from which such acts are supposed to proceed.  I shall, therefore, in the sequel of this work, say little or nothing of ‘conscience’ or ‘moral sense,’ not because I think it desirable to banish those words from popular terminology, but because I think that, in an attempt to present the principles of ethics in a scientific form, they introduce needless complexity and obscurity.