I can conceive him placed in such a situation that he is not much tempted to deviate from what is right; and as every man prefers virtue, when there is not some strong incitement to transgress its precepts, I can conceive him doing nothing wrong. But if such a man stood in need of money, I should not like to trust him; and I should certainly not trust him with young ladies, for there there is always temptation.28

This conviction, that a morality based upon the affections might not serve to support us in those hard cases which are the test of any morality, led Johnson also to oppose speculative theories which tended to diminish man’s responsibility for his moral health – for example, fashionable theories which related morals to climate, or which located the cause of moral degeneration in broad social phenomena such as luxury. A good example of Johnson’s resistance to anything which suggested that moral judgements were not peculiarly human, and rooted in the conscious will, is his refusal even to entertain one of Boswell’s experiences while on the Grand Tour:

I told him that I had several times, when in Italy, seen the experiment of placing a scorpion within a circle of burning coals; that it ran round and round in extreme pain; and finding no way to escape, retired to the centre, and like a true Stoick philosopher, darted its sting into its head, and thus at once freed itself from its woes…. I said, this was a curious fact, as it shewed deliberate suicide in a reptile.29

Johnson refused point blank to accept the possibility of a reptile’s committing suicide, because he could admit neither that animals possess a moral sense, nor that an authentically ethical act could be a reflex, without sacrificing the essence of his moral position; namely, that our moral sense is the product of our waking judgement.

Given that Johnson was such an advocate for an ethics of conscious principle, one would expect his ethical language to be overt and declaratory; that is to say, conscious, stated and argued for. But the experience of reading Johnson is, I think, not like that. Sir John Hawkins caught well how the impact of Johnson’s writing is not one of propositional clarity:

In all Johnson’s disquisitions, whether argumentative or critical, there is a certain even-handed justice that leaves the mind in a strange perplexity.

‘A strange perplexity’: it is precisely that sense of being moved at a level beyond or beneath the level of language which, I think, characterizes the experience of reading Johnson’s best moral writing. To understand why this should be so, we need to consider the theory of language which exerted the greatest influence over Johnson, that elaborated by John Locke in Book III of An Essay Concerning Human Understanding.

The importance of language for Locke was that, since words represent ideas, not objects, they can form the conduit of knowledge:

… it was further necessary that he [man] should be able to use these sounds as signs of internal conceptions, and to make them stand as marks for the ideas within his own mind, whereby they might be made known to others, and the thoughts of men’s minds be conveyed from one to another.30

The ideas that language could convey are of two kinds, simple and complex. An example of a simple idea would be ‘goat’. Simple ideas, Locke insisted, cannot be defined. However, in practice this is not a great problem since they can be demonstrated or pointed out. An example of a complex idea (or ‘mixed mode’, as Locke more often calls it) would be ‘ingratitude’ (and indeed the ideas represented by all ethical language fall into this category of mixed modes). For mixed modes, the reverse holds true. They cannot be demonstrated, because, in Locke’s words, ‘they are the creatures of the understanding rather than the works of nature’.31 However, the compensation for this is that they can be defined with perfect precision:

… the signification of their names [those of mixed modes] cannot be made known, as those of simple ideas, by any showing, but, in recompense thereof, may be perfectly and exactly defined. For they being combinations of several ideas that the mind of man has arbitrarily put together, without reference to any archetypes [i.e. things existing in nature which form the original patterns of those ideas], men may, if they please, exactly know the ideas that go to each composition, and so both use these words in a certain and undoubted signification, and perfectly declare, when there is occasion, what they stand for.32

For Locke, this is a source of great comfort, because from it he deduces that moral language can be made more precise than any other kind of language:

This, if well considered, would lay great blame on those who make not their discourses about moral things very clear and distinct. For since the precise signification of the names of mixed modes… is to be known, they being not of nature’s but man’s making, it is a great negligence and perverseness to discourse of moral things with uncertainty and obscurity… Upon this ground it is that I am bold to think that morality is capable of demonstration, as well as mathematics: since the precise real essence of the things moral words stand for may be perfectly known, and so the congruity or incongruity of the things themselves be certainly discovered, in which consists perfect knowledge.33

Johnson’s famous comment – ‘words are the daughters of earth, and… things are the sons of heaven. Language is only the instrument of science and words are but the signs of ideas’ – shows his affinity with Locke’s theory of language.34 But on this point of the demonstrability of morality, he is at the opposite pole from his philosophical predecessor. What Locke saw as a source of encouragement – that moral terms are susceptible of exact definition – Johnson, as a practical rather than a speculative moralist, found a cause of disquiet. It may be that such moral terms can be precisely defined. But those precise definitions may not help in the practical business of grasping the substantive essence of moral ideas.

The point can be clarified if we compare definitions from the Dictionary of what Locke would have called simple ideas with mixed modes. First, two definitions of simple ideas:

Horse: A neighing quadruped, used in war, in draught, and in carriage.

Ink: The black liquor with which men write.

These definitions follow on from Locke’s insistence on the demonstrability of a simple idea, in that they take the form of a set of instructions as to where to look. If you want to know what ink is, you find a man who is writing, and look at the black liquor he is using. Johnson’s definitions of mixed modes are quite different:

Virtue: Moral goodness: opposed to vice.

Vice: The course of action opposite to virtue.

Good: Not bad; not ill.

Ill: Not well.

It is quite clear that, considered purely as definitions, these have a precision which the definitions of ‘horse’ and ‘ink’ lack; but it is hard to see what use they are to someone who wishes to lead a moral life, and therefore needs to know the content of the ideas these terms represent. Locke had assumed that, because these words could be precisely defined, we could have exact knowledge of the essence of the idea. But for Johnson, it is possible to have a precision of moral language, but nothing else, as he shows in the character of the philosopher in chapter twenty-two of Rasselas:

To live according to nature, is to act always with due regard to the fitness arising from the relations and qualities of causes and effects; to concur with the great and unchangeable scheme of universal felicity; to co-operate with the general disposition and tendency of the present system of things.35

For Johnson, to live a moral life was less a question of possessing a vocabulary than of performing actions. In Rambler No. 14 he acknowledged the power of moral theory: ‘in moral discussions it is to be remembered that many impediments obstruct our practice, which very easily give way to theory’.36 But that power will be only a snare and a delusion unless it be also remembered that ‘human experience, which is constantly contradicting theory, is the great test of truth’.37 How can language lay hold on the substance of morality, instead of shadowing the world of moral action with a self-regarding and futile precision?38

It is here that Johnson’s notion of the special virtue of poetic language is important. In Idler No. 60 Johnson amusingly mocked Dick Minim’s enactment theory of poetic language. He was obliged to do so in order to distinguish that crassness from a notion of poetic language which he took very seriously: namely, that ‘the force of poetry’ ‘calls new powers into being’, which powers are capable of ‘embod[ying] sentiment’, including moral sentiment.39 If we turn now to his poem on Robert Levet, we can see an example of that force and of those powers at work.

Boswell gave a disdainful sketch of Levet: ‘he was of a strange grotesque appearance, stiff and formal in his manner, and seldom said a word while any company was present.’40 From this unpromising material, Johnson made a moral poem of extraordinary force.