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In predicate logic, does existential qualification (∃) include universal quantification (∀), i.e. can 'some' imply 'all'?

I am having a discussion wether 'some' can also imply 'all'. The definition for some, 'an unspecified number or amount of people or things' seems to leave room for this interpretation.

Discussion follows on the following statements:

1. All newspaper readers are reasonable people.

2. Some newspaper readers are criminal.

The question is whether or not the statement:

Not all reasonable people are criminal

Is valid or not...