Sonnet CXLVII

My love is as a fever longing still,
For that which longer nurseth the disease;
Feeding on that which doth preserve the ill,
The uncertain sickly appetite to please.
My reason, the physician to my love,
Angry that his prescriptions are not kept,
Hath left me, and I desperate now approve
Desire is death, which physic did except.
Past cure I am, now Reason is past care,
And frantic-mad with evermore unrest;
My thoughts and my discourse as madmen's are,
At random from the truth vainly expressed;
   For I have sworn thee fair, and thought thee bright,
   Who art as black as hell, as dark as night.

Perhaps as a natural continuation of the renunciation of the previous sonnet, or perhaps independently of it, the poet here reflects on his woeful state. He is like a patient in a fever who has been declared by the physician to be past cure. All his thoughts and words are like those of madmen, and everything is uttered at random, without any coherence. His fever lends him words, and although he cannot explain his infatuation, he feels it to be wrong, and yet he is compelled to continue drinking and eating the same noxious food which brought on his disease in the first place. Hence there is no escape for him, and he sees himself trapped in the black vortex of hell in which his mistress resides, and there is no release from the darkness.

The 1609 Quarto Version

MY loue is as a feauer longing ſtill,
For that which longer nurſeth the diſeaſe,
Feeding on that which doth preſerue the ill,
Th'vncertaine ſicklie appetite to pleaſe:
My reaſon the Phiſition to my loue,
Angry that his preſcriptions are not kept
Hath left me,and I deſperate now approoue,
Deſire is death,which Phiſick did except .
Paſt cure I am,now Reaſon is paſt care,
And frantick madde with euer-more vnreſt,
My thoughts and my diſcourſe as mad mens are,
At randon from the truth vainely expreſt.
   For I haue ſworne thee faire,and thought thee                                                                                  bright,
   Who art as black as hell,as darke as night.

Commentary

1. My love is as a fever longing still,
My love = my passion for you, my infatuation.
longing still = constantly desiring, incessantly eager.
fever - A term often associated with love which Shakespeare has already used in connection with his aberrant behaviour when he appeared to have deserted the youth and distracted himself with other loves:
How have mine eyes out of their spheres been fitted
In the distraction of this madding fever!
119.
Medically a fever was 'an vnnaturall heate grounded in the hearte and lyuer'. (OED cites this from 1547). Given the uncertain knowledge of the time, it could be applied to almost any illness. The usual treatment would be blood letting, which was supposed to reduce the inner pressures and temperature:
DUM. I would forget her; but a fever she
Reigns in my blood and will remembered be.
BIR. A fever in your blood! why, then incision
Would let her out in saucers: sweet misprision!
LLL.IV.3.91-4.
Since fever brought on ravings, there was a widespread belief that the sick persons always irrationally desired the thing which was no good for them. They might wish for fruit or drinks for example, which the physician would consider to be unsuitable and damaging to the health. Hence the prescription (line 6) could be, as well as medicine, a prohibition against the consumption of these supposedly undesirable foods. Compare :
...................and your affections are
A sick man's appetite, who desires most that
Which would increase his evil.
COR.I.1.173-5.
2. For that which longer nurseth the disease;
longer = for a longer time. The proximity of longing and longer makes it seem as if the patient longs to prolong his illness.
that which etc. = the unsuitable food or drink which caused the disease initially.
nurseth
= nurses. The word is ambiguous, for it suggests two opposites, 'brings back to health', and 'tends carefully, so that it (the illness) stays'.
3. Feeding on that which doth preserve the ill,
Feeding on - i.e. his love is feeding on the forbidden fruit.
which doth preserve the ill = which causes the illness to remain.
4. The uncertain sickly appetite to please.
(In order to) satisfy my wavering, distempered desires.
appetite = desire for food. But, in the context of a diseased love, it signifies lust, carnal desire. OED.3 gives: 'one of those instinctive cravings which secure the preservation of the individual and the race'. Shakespeare's use of the word is often rather stronger and more specific than OED indicates, as the following three extracts show:

Behold yond simpering dame,
Whose face between her forks presages snow;
That minces virtue, and does shake the head
To hear of pleasure's name;
The fitchew, nor the soiled horse, goes to 't
With a more riotous appetite.
KL.IV.6.118-23.

Moreover, urge his hateful luxury
And bestial appetite in change of lust;
R3.III.5.80-1.

There is no woman's sides
Can bide the beating of so strong a passion
As love doth give my heart; no woman's heart
So big, to hold so much; they lack retention
Alas, their love may be called appetite,
No motion of the liver, but the palate,
That suffer surfeit, cloyment and revolt;
TN.II.4.92-8.

The subject of the line is 'my love, which is like a fever' (line 1). Note that the word order is inverted - 'in order to please the sickly appetite'.

5. My reason, the physician to my love,

My reason - one of the faculties of the soul. Its presence here, as also the feeding metaphors, help to tie this poem in with the previous one.
the physician = the doctor. The two words were used by Shakespeare without distinction. Shakespeare's daughter Susanna married the physician John Hall in 1607.

6. Angry that his prescriptions are not kept,
prescriptions = rules of good health, the regimen given as a means of curing a disease, proscriptions (i.e. orders to avoid certain things). In more recent use the word came to mean 'the medicine (which had been written down by the doctor)'.
kept
= observed, obeyed. As in 'to keep one's promise'.
7. Hath left me, and I desperate now approve
Hath left me - i.e. my reason has left me.
I desperate
= I, having become desperate; in desperation, I etc.
approve
= demonstrate, show by my experience, give proof that.
8. Desire is death, which physic did except.
A line of uncertain meaning which is variously glossed. 'Desire, such as I experience it, will bring my death, although the appropriate medicine would have averted it'. 'Any desire which militates against good medical practice brings death to the patient'. 'Sexual desire shortens life, but medicine can allay the effects of it'. 'Sexual desire under certain conditions which would cause physicians to forbid it, will prove fatal'. The difficulty is partly in the word 'except', but also in the compression of 'desire is death'. except probably means here 'took exception to'. (See SB.p.518-9). There was a belief that every orgasm shortened one's life by a day. There may also be a reference to venereal disease in 'desire is death'. It was widespread and often fatal. See the note below to line 13.
9. Past cure I am, now Reason is past care,
An echo of the proverb 'Past cure past care', meaning that when curative remedies have been exhausted to no effect, there is no point in worrying any further, but also equivalent to the more humdrum 'Don't cry over spilt milk'. Shakespeare has inverted it by saying 'Reason is past care i.e. beyond hope, therefore I am past cure'.
10. And frantic-mad with evermore unrest;
And frantic mad = and I am frantically mad; I have become frantic. Note that Q's spelling of 'mad' as 'madde' allows a confusion with made. Thus 'I have been made frantic by my love for you'. The spelling of 'mad' in the following line is conventional.
evermore unrest
= unrest which is incessant and endless. Evermore seems here to have an adverbial force, but if taken as two words, 'ever more', it could mean unrest, disquiet, which is continually increasing.
11. My thoughts and my discourse as madmen's are,
There is a feverish quality to these two lines, in keeping with the theme of fever introduced at the start. He no longer knows what he is saying or if his thoughts have any meaning.
my discourse
= my speech; my reasoning, my faculty of reasoned speech. As in:
O, God! a beast, that wants discourse of reason,
Would have mourned longer Ham
.I.2.150-1.
where wants = lacks.
as madmen's are
- i.e. my speech is like madmen's speech.
12. At random from the truth vainly expressed;
random - Q's randon was a variant of the time, based on the French word meaning 'headlong, in a violent rush'.
at random from the truth
= wide of the truth, straying erratically and irrationally from the truth, furiously rushing from the truth.
vainly expressed
= spoken to no purpose, spoken with foolhardiness.
13. For I have sworn thee fair, and thought thee bright,
The couplet explains how he has strayed at random from the truth, for he has sworn that his beloved is something which she is not, that she is fair and beautiful, when she in fact is dark and benighted. The most disturbing aspect of these concluding lines is that they are so brutal and unforgiving. The epithets have both physical and moral significance, for he seems determined to prove that she was not beautiful either in soul or body. There was indeed a tradition within the sonneteering world at the time that the beloved was not always as fair as Petrarch's fairest Laura. But it was essentially a playful tradition, in that there was a determination to find something different to look at. Robert Tofte, for example, in 1597, declares
"My mistress seems but brown", say you to me.
'Tis very true, and I confess the same.
..................
This is the cause: for brown and pitiful
I left a fair, but yet a faithless Trull. Laura III.31.
But Shakespeare's sonnet breaks off from that tradition, for it heaps vilification on the beloved as if she were a tart. For Tofte the faithless Trull was the one he had left, not the one he was busy praising at the moment. Whereas here the poet loves, or pretends to love, what he finds dark, black, bestial, and morally unfathomable. It is tempting to ask whether or not this is his madness speaking, whether or not he is as guiltless as we might assume, whether or not the man who left to his wife the second best bed night not have been a swine with women. For it is not impossible that the writer who gave the world some of the finest women ever created in fiction should be unable to form a satisfactory relationship with them in his life. The harsh judgement which here he levies upon his mistress, as he does also, but less vitriolically, in 131,137 and 152, does not seem to have caused too much disturbance, even among female critics, who, one would expect, might be more sensitive to these possibilities. (KDJ and HV for example both comment on this sonnet unecstatically and with little sense of discomfort at its content, except perhaps by excusing it as mad ravings). Yet it is surely appropriate to ask for whom the sonnet was intended. Was it one of the sugared sonnets among his private friends, was it intended for his mistress, or was it for the wider world, the public who might read eventually the full sequence? All these possibilities fill one with a sense of unease, and however much one might wish to praise the poem for its unfailing honesty, one wonders whether that is really a sufficient justification for its cruelty.
Alternatively we could perhaps look for a mundane explanation, and see this as the meanderings of someone who is suffering from a bad dose of the pox. The closing line, with its suggestions of hell and darkness, is, as always, suggestive of the female hell, the vagina, which burns with the flame of venereal disease, as in Timon of Athen's outburst:
...............................................be whores still;
And he whose pious breath seeks to convert you,
Be strong in whore, allure him, burn him up;
Let your close fire predominate his smoke,
And be no turncoats:
Tim.IV.3.139-43.
The essential condition for cure of the illness was obviously abstention from intercourse, which the poet does not seem to be able to manage, and the physician despairs of him. Apart from that, treatment was possible by 'suffumigation with cinnabar in a meat-pickling vat', an experience not likely to be very pleasant. The patient was at the same time kept on a low diet. After such a cure anyone might well feel dejected and low and be capable of writing a sour sonnet or two about his mistress.
14. Who art as black as hell, as dark as night.

See note above. The blackness of hell and the darkness of night, and vice versa, were proverbial attributes.

 

Bacchante (Lady Hamilton) after George Romney.  Published 1797. 

Bacchante