Under Section 59 of the Indian Succession Act, 1925, what are the comprehensive requirements for testamentary capacity?

Section 59 of the Indian Succession Act, 1925, establishes a multi-factor testamentary capacity test: (1) testator must be 18 years or above, (2) of sound disposing mind when executing the will, (3) understand the nature and effect of the will, (4) know the extent and character of property being disposed, (5) understand just claims of family members and dependents upon the testator, and (6) be free from mental disorder clouding judgment. Courts apply this stringent test to prevent improvident dispositions. Mental capacity at will-making time is essential; capacity at other times is irrelevant. Medical evidence, testator's behavior, and beneficiary relationships are examined to determine capacity.