What explanation does Hinduism give for not touching books and people with feet?

Kids born and brought up in India undergo a certain list of rules and regulations which every Indian born child is a must to learn and apply those rules in his or her daily lives. These rules and regulations are not mere rules but the cultural roots of India. Every parent in India wants their kids to learn and follow what they have learnt from their parents and this moves on to each generation.

One such custom is worshipping Books and elderly people. We in India never touch books, papers, any written material or elderly people with our feet (even by mistake). Touching books or another human with your feet is considered the same as disrespecting the Lord within him or her. An immediate apology should be offered with reverence and humility. Even when elders touch a younger person inadvertently with their feet, they immediately apologize.

The custom of not stepping on educational tools is basically a reminder of the importance and significance of Knowledge in the Indian culture. We believe that Goddess Saraswati resides in Books that grant us education and fill knowledge within us. Stepping books with our feet, is insulting Saraswati herself. Each student in every house is taught with this sloka, to teach the importance of education in one’s life:

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Saraswati namasthubhyam
Varade kaama roopini
Vidyaarambham karishyaami
Sidhirbhavatu me sadaa

O Goddess Saraswati, the giver of Boons and fulfill-er of wishes, I prostate to You before starting my studies. May you always fulfill me.

Yaa daevee sthooyathae nithyam vibhudhair vaeda paaragaih
Saa mae vasathu jihvaagrae brahmaroopaa saraswathi

May Saraswathi, the Goddess of knowledge, who is ever praised by the wise, who have mastered the scriptures, who is the embodiment of the Vedas ( or the consort of Lord Brahma ), live on the tip of my tongue.

Why are We Forbidden from touching People with our Feet ?

Not just touching, Indians are not allowed to even point their feet towards any person elderly to them.The reason for this is very simple. Our feet are very unclean. The dirt on our feet makes it bad to touch anyone with our feet.

The reason why Indians are prohibited from even pointing their feet to any person is that it gives a very bad impression to the person. It shows that you do not have any respect for that person. According to the Indian tradition and culture, It is bad manners to do so.

Thus, many of our customs may be designed to be simple though are powerful reminders or pointers of profound philosophical truths. This one reason has kept Indian culture and its customs alive throughout centuries.