In order to purchase life insurance I am told I must have an 'insurable interest' in the person to be insured. What is 'insurable interest'?

 The Insurance law defines 'insurable interest' as, in the case of persons closely related by blood or by law, a substantial interest engendered by love and affection. In the case of other persons, a lawful and substantial economic interest in the continued life, health or bodily safety of the person insured, as distinguished from an interest which would arise only by, or would be enhanced in value by, the death, disablement or injury of the insured.

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Life Insurance Resource Center
Comprehensive information about life insurance from the Insurance Department's Life Insurance Resource Center
URL: http://www.dfs.ny.gov/insurance/clife.htm