Sonnet 147

Love is a self-perpetuating fever: the beloved feeds the disease while reason, like a frustrated physician, abandons the hopeless patient.

Original
Modern
1 My love is as a fever longing still,
central metaphor: love as fever
My love is like a fever that continues to crave
2 For that which longer nurseth the disease,
Craving for what prolongs the illness
3 Feeding on that which doth preserve the ill,
Consuming what sustains the illness
4 Th’ uncertain sickly appetite to please:
To satisfy an uncertain, sickly craving
5 My reason the physician to my love,
My reason is the doctor attending my love
6 Angry that his prescriptions are not kept
Angry that his prescribed treatment is not being followed
7 Hath left me, and I desperate now approve,
Has abandoned me, and I now desperately approve
8 Desire is death, which physic did except.
Desire is death, which the medicine forbade
Volta The volta shifts from medical metaphor to madness: reason abandons him, and he is left 'frantic-mad' without restraint or truth.
9 Past cure I am, now reason is past care,
I am beyond healing, now reason has stopped caring
10 And frantic-mad with evermore unrest,
And maddened with endless agitation
11 My thoughts and my discourse as mad men’s are,
My thoughts and speech are like a madman's
12 At random from the truth vainly expressed.
Spoken randomly, far from truth, expressed uselessly
13 For I have sworn thee fair, and thought thee bright,
I have sworn you are beautiful and believed you were brilliant
14 Who art as black as hell, as dark as night.
Yet you are as dark as hell, as dark as night
Love as Pathology

Shakespeare employs detailed medical language: fever (disease), nurseth (metaphor of feeding), physician (reason), prescriptions (rational counsel), physic (medicine/cure). Love actively works against healing because the lover craves the beloved as a fever patient craves what worsens the condition. The metaphor implies love is literally a sickness of the body, not merely emotion.

Madness and Truth

Lines 11–12 declare the speaker's thoughts 'as mad men's are,' expressed 'at random from the truth.' Yet madness reveals truth: in the couplet, he admits she is objectively 'black' and 'dark.' Irrationality and delusion are what allowed him to call her 'fair' and 'bright'; sanity reverses the lie. This is psychologically astute: love and madness are one.

If this happened today

Like someone addicted to a toxic relationship—they know it's poisoning them but they crave the poison. Each fight, each cruelty, paradoxically deepens the attachment. The rational part of them has given up; madness is all that's left.