According to scholar Roy Mottahedeh, one significant change to Islam in Iran during the first half of the 20th century was that the class of ulema lost its informality that allowed it to include everyone from the highly trained jurist to the "shopkeeper who spent one afternoon a week memorizing and transmitting a few traditions." Laws by Reza Shah that requiring military service and dress in European-style clothes for Iranians, gave talebeh and mullahs exemptions, but only if they passed specific examinations proving their learnedness, thus excluding less educated clerics.