The survey was conducted by using Implicit Association Test (IAT) and explicit instruments to more than 2,000 teachers, complemented by in-depth interviews with at least 60 teachers in five cities. The highly comprehensive study found that more than 63 percent of teachers have intolerant opinion towards other religious adherents by using IAT, while the percentage was around 50% when using the explicit instrument. The survey, titled ‘The Dimming Light’, discovered that the relatively high number of intolerant teachers in Indonesia is mainly influenced by three factors. The first factor is Islamism worldview; teachers who are intolerant mostly prefer application of Islamic jurisprudence in all areas of their lives, including politics; emphasizing on the importance of making the sharia as the highest source of law in all aspects of life. They also use this perspective in viewing education by agreeing that Muslims no longer need to study knowledge from the West as all knowledge can be found in the Quran. Secondly, demographic factors are important in understanding intolerance and radicalism among teachers. The survey found that female teachers tend to have more intolerant opinions that male teachers. Furthermore, teachers with lower income also tend to be more intolerant. The third factor that also needs to be taken into account is their affiliation to religious mass organizations. Teachers which affiliate themselves with certain mass organizations and also certain religious figures tend to be more radical.