The criminological positivists at the turn of the century started a good deal of creative rethinking about the criminal law. Some of their proposals have gained widespread acceptance in the criminal law as we know it today. Others made no headway at all. One particular proposal, and a very fundamental one indeed, began a controversy which has ebbed and flowed regularly since. That is the proposal to eliminate from the criminal law the whole apparatus of substantive principles, or at least some of them, such as the legal insanity defence, which owe their presence to the law's traditional concern for distinguishing the guilty and the innocent in terms of their blameworthiness. The essence of the proposal is that innocence in this sense, moral innocence, if you will, should not disqualify a person from the consequences of the penal law. Moral innocence should, it is urged, give way to social dangerousness as the basis for a criminal disposition.