Hinduism is not built on faith. It approaches the space and time with most modern and futuristic concepts and relates it to our day to day living. It could be possible that ancient saints heard it (श्रुति) and passed it on to us or they conceptualized an infinitely powerful embodiment Brahman from which everything originated. Naturally such a concept will not only will have to be scientifically correct, but also atheistic (Atheism is, in a broad sense, the rejection of belief in the existence of deities. For more from wikipedia ). The concepts have to correlate with our ethics and morals and form the base of society. Here are some evidences to show how it has been done. The Keno Upanishad says repeatedly that Brahman the creator of universe in is not our concept of God whom we pray to (It does not even bother to ask whom we are praying to), not once but many times.
Similarly our study of Ramayana also shows no god but only dharma which binds our society. More on this concept to follow
ॐ केनेषितं पतति प्रेषितं मनः केन प्राणः प्रतमः प्रैति युक्तः
केनेषितां वाचमिमां वदन्ति चक्षुः क्षोत्रं क उ देवो युनक्ति 1
क्षोत्रस्य क्षोत्रं मनसो मनो यद् वचो ह वाचं स उ परस्य प्राणः
न तत्र चक्षुर्गhच्छति न वागच्छति नो मनः
अन्यदेव तव्दिदितदथो अविदि तादधि
यद्वाचाऽनब्युदितं येन वगब्युद्यते
येन्मनसा न मनुते येन हुर्मनो मतम्
यच्चक्षुषा न पश्यति येन चक्षूंषि पश्यति
यच्छोत्रेण न शृणोति येन श्रोत्रमिदं श्रुतं
यत्प्राणेन न प्रणिति येन प्राणः प्रणीयते
By whose commands this mind works? By whose will the life’s breath circulates? Who is responsible for man’s speech? What intelligence does lead the eyes and the ears? 1
It is the ear of the ear, the mind of the mind, the speech of the speech. Also the life of all life, and the eye of the eye.
The wise abandon the sensory world and become immortal. 2
There the eyes cannot travel, nor speech nor mind. Nor do we know how to explain it to the disciples.3
It is other than the known and beyond the unknown. So were we taught by our ancients. 4
That which the speech cannot reveal, but causes the speech to flow, know that alone to be Brahman, not this whom people worship here 5
(through mantras). That which the mind cannot conceptualize, but by which the mind does conceptualize, know that alone to be Brahman, not this whom people worship here. 6
That which the eye cannot see, but by which the eyes are able to see, know that alone to be Brahman, not this whom people worship here 7.
That which the ear cannot hear, but by whom the ear can hear, know that alone to be Brahman, not this whom people worship here 8.
That which one does not breath, but by whom air is breathed, know that alone to be Brahman, not this whom people worship here 9.