Islam emerged in the Arabian Peninsula about 1400 years ago. Central to the religion is the belief that there is one and only one god, Allah, and that Muhammad, a 7th century merchant-turned-religious leader, was his finest and last prophet.
As things presently stand, slightly more than 23% of the world's population believes in Islam. This comes out to about 1.7 billion people as of the middle of 2015. What do Muslims believe and value? Polling conducted by the Pew Research Center has taken an introductory look at this question.
While Pew's research has been carried out in almost 40 countries, it's worth noting that it did not include India, Western Europe, Iran, Saudi Arabia, Yemen, and a number of other countries in the Middle East, Africa, and elsewhere. As such, their findings statistically represent the views of, at most, around 1.15 billion of the roughly 1.7 billion Muslims in the world.
If we combine data from the Pew surveys with information about population sizes and the percentage of Muslims within the counties polled, though, it is possible to calculate how many Muslims believe something as a concrete figure. The results are below.
Wide consensus exists on the question of the immorality of unmarried sex and homosexuality. Out of more than a billion Muslims in 36 countries, 88% regard sex outside of marriage as immoral, while 89% regard homosexual sex as immoral.
The only poll questions on which greater consensus exists among Muslims relates to the belief that there is one god, Allah, and that Muhammad is his prophet (97%) and that angels exist (92%). After that, the next most agreed-upon thing is that homosexuality and unmarried sex are immoral.
For comparison, research published in 2013 by Pew indicates that 60% of people in the United States, 80% in Canada, 79% in Australia, 76% in Britain, 60% in Brazil, 21% in China, and 16% in Russia think homosexuality should be socially accepted.
The maximum number of wives a male is permitted to have in Islam is four (Muhammad was an exception, and was granted rights by god to have as many wives as he pleased). Though permitted, the Quran says that a man should have more than one wife if he can treat them all fairly and equally. It then proceeds to say that they will not be able to do that, implying that a man should not actually have more than one wife.
The majority of Muslims represented in the survey (68%) think that women should have the right to choose whether they wear the veil or not. A majority (86%) also completely or mostly agree that a wife must always obey her husband.
These responses can be taken as evidence of a kind of conflict or tension embedded in the values of Muslims concerning female autonomy. It is worth emphasizing that these questions were asked of both male and female respondents.
Muslims who prefer democracy
Muslims who prefer a strong leader