"The bedrock of Periyar’s principles and the movements that he started was rationalism. What drew him to public service and made him dedicate his life to it was man’s inhumanity to man. He found that an insignificant minority in society was exploiting the majority and trying to keep them in a subordinate position forever. To set matters right, he wanted the exploited to sit up and think about their position. Unless they exercised their reason, there wouldn't be a realization that they were being exploited by a handful of people. If they started thinking, they would realize that they were human beings like the rest, that birth did not and should not endow superiority over others, and that they must awaken themselves and do everything possible to improve their own lot.
It was not an easy task for Periyar to create this awakening among the people who had, for generations, got used to a subordinate position. Most of them did not know that their subordinate position had been brought about by the cunning schemes of self-seekers. Thus, Periyar spoke to the people on innumerable platforms, over the years to arouse their thinking power.
Likewise, Periyar explained that wisdom lies in thinking and that the spear-head of thinking is rationalism. On caste, he stated that no other living being harms or degrades its own class. But man, said to be a rational living being does these evils. The differences, hatred, enmity, degradation, poverty, and wickedness, now prevalent in the society are due to lack of wisdom and rationalism and not due to God or the cruelty of time.
Periyar also blamed the capitalists for their control of machineries, creating difficulties to the workers. Consequently rationalism, which has to lead the way for peaceful life to all, had resulted in causing poverty and worries to the people because of dominating forces. He went on to explain that there is no use of simply acquiring titles or amassing wealth if one has no self-respect and scientific knowledge. An example he showed was the West sending messages to the planets, while the Tamil society in India were sending rice and cereals to their dead fore-fathers through the Brahmins.
In a message to the Brahmin community, Periyar stated, "in the name of god, religion, and sastras you have duped us. We were the ruling people. Stop this life of cheating us from this year. Give room for rationalism and humanism". He further explained that "any opposition not based on rationalism, science, or experience will one day or another, reveal the fraud, selfishness, lies and conspiracies"."
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