A madman can transact no business, because he does not understand what he does.

Explanation

Legal capacity requires a sound mind — no transaction by one who cannot comprehend the nature and effect of his act has any validity. This applies to contracts, conveyances, wills, and every other legal act without exception.

Where this applies

• My aunt was diagnosed with severe dementia before she wrote her will — is it valid?
• A mentally incapacitated person signed a new will — can that be challenged?

See also

• 3.1.1 A person is a man considered in light of a certain status.
• 5.7.2 In wills, the intention of the testator is more especially regarded.