Let's take a look at what Jerald Block said. He identifies three "subtypes" of internet addiction: excessive gaming, sexual preoccupations, and e-mail/text messaging (not strictly internet, I know).

Want to know if you're addicted? He provides these four criteria:

1. Excessive use, often associated with a loss of sense of time or a neglect of basic drives
2. Withdrawal, including feelings of anger, tension, and/or depression when the computer is inaccessible
3. Tolerance, including the need for better computer equipment, more software, or more hours of use
4. Negative repercussions, including arguments, lying, poor achievement, social isolation, and fatigue

Ignoring the sex and gaming addicts, aren't rather a lot of people email/text messaging addicts according to this scheme?

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