Answer
Epicurus, an ancient Greek philosopher, profoundly influenced Michel Onfray's "Atheist Manifesto." His philosophy advocated for a life free from fear and pain, emphasizing tranquility, pleasure, and the absence of divine intervention in human affairs. Epicurus's ideas, particularly his emphasis on personal freedom and the pursuit of happiness, resonate deeply within Onfray's exploration of atheism and the construction of a meaningful existence without the need for religious belief.