Man is different from other animals because of his ability to think; as far as our knowledge is concerned, other animals and birds cannot think. It is the thought process which makes one different from other human beings.
The thought process happens with the help of ideas; an idea refers to an understanding or picture in the mind. An idea exists in mind as a form or a sound. Smell, touch and taste are functioning along with the form; Therefore, form and sound are the basic elements for the formation of ideas. Verbal language naturally follows the formation of form and sound. Whether it is a form or a sound, both are received and recognised in the mind with the association of verbal language.
The thinking in the human mind is either questioning or answering; it is either a question for an answer or an answer to a question. This awareness is helpful to initiate the thinking process on any subject. If you want to initiate a thinking process about an elephant, you only need to ask certain questions about elephants. What is the colour of the skin of an elephant? Where do they generally live? What do they eat? How long is the average lifespan of elephants? How can they be tamed? What are the fields where elephants are used commercially? Why are elephants decorated and engaged for carrying the idol of deities in temple festivals? How close is the friendship of human beings and elephants? Answers to these questions form a wonderful article on elephants.
The questions and answers in the thinking process should be based on a subject which is called food for thought. Some food items for thought may not be nutritious just like junk food to the stomach. Some are unhealthy for the thinking mind, similar to rotten food items; they ruin the right way of approach and clear understanding and lead the thinker towards destructive conclusions. Such ideas are called Asura Sampat (the group of destructive ideas) in Bhagavad Gita. There are good ideas like nutritious food to the body; they can be considered as healthy food to thought which are named as Daiva Sampat (the group of constructive ideas).
Man lives with the food for thought. Nutritious food is inevitable for the body; similarly, good food for thought is also necessary for a healthy life. Bhagavad Gita categorises ideas as Daiva Sampat and Asura Sampat (groups of constructive and destructive ideas). The constructive ideas are grouped in Bhagavad Gita as follows:
Fearlessness,
Purity of mind,
Persistence in knowledge and Yoga,
Charity and control of the external organs,
Affinity towards selfless service,
Scriptural study,
Austerity,
Rectitude. (Chapter 16, Sloka 01)
Absence of hatred,
Truthfulness,
Absence of anger,
Renunciation,
Control of the internal organ,
Absence of vilification,
Kindness to creatures,
Non-covetousness,
Gentleness,
Modesty,
Freedom from restlessness. (Chapter 16 Sloka 02)
Vigour,
Forgiveness,
Fortitude,
Purity,
Freedom from malice,
Absence of haughtiness.
These are the qualities of one born destined to have constructive ideas. (Chapter 16, Sloka 03)
These ideas live in the mind of a good person to influence his thoughts and decisions at any time. He is nourished with these ideas in his thoughts and behaviour. For example, the one who takes ‘absence of hatred’ as food for thought, through constant thinking and self enquiry, that idea would get digested in him; that idea would be a natural part of his mind; he would approach any situation with a hatred-free mind; he thinks in that way; he would behave to others accordingly; People speak about him that he would not hate anybody. This is as a result of his acceptance of the idea of ‘absence of hatred’ as a food for thought. The idea which is active in the mind would appear in memory from time to time and would influence all activities of the individual. Therefore, an individual should choose constructive ideas, rather than destructive ones, to cultivate in his thoughts through continuous self enquiry and frequent repeated reflection.
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abhayam satvasamśuddhiḥ jñānayoga vyavasthitiḥ
dānam damaśca yajñaśca svāddhyāyastapa ārjavam (Gita Ch 16 - Sloka 1)
ahimsā satyam akrodhastyāgaḥ śāntirapaiśunam
dayā bhūteṣvaloluptam mārdavam hrīracāpalam (Gita Ch 16 - Sloka 2)
tejaḥ kṣamā dhṛtiḥ śaucam adroho nātimānitā
bhavanti sampadam daivīm abhijātasya bhārata (Gita Ch 16 - Sloka 3)