Season 13

यदा भूतपृथग्भावमेकस्थमनुपश्यति ।तत एव च विस्तारं ब्रह्म सम्पद्यते तदा ॥३१॥
"When a sensible man ceases to see different identities, which are due to different material bodies, he attains to the Brahman conception. Thus he sees that beings are expanded everywhere."
Do we see different identities? Man, woman, young, old, Mr. John, Ms. Nixon. Then we are not sensible as per Lord Krishna. Seeing different identities is illusion. But bodies are not false. Lord Krishna explains the simulated reality and the origin of consciousness at the end of 13th Chapter.

प्रकृत्यैव च कर्माणि क्रियमाणानि सर्वशः ।
यः पश्यति तथात्मानमकर्तारं स पश्यति ॥३०॥
"One who can see that all activities are performed by the body, which is created of material nature, and sees that the self does nothing, actually sees"
Sun and Moon appear small balls in the sky but through science we know their real magnitude.
Animals always trust their perception, but a human being is supposed to see things beyond one's often misleading perception and develop scientific understanding of reality. 

As we leave our old vehicle and start using new one, similarly the soul leaves the body when it is no longer usable and enters another new one. Reincarnation is a very important fact which is not taught in modern education but which was scientifically explained by Lord Krishna to Arjuna. Our endeavours should not just be directed towards maintenance of current body but more importantly we must know how to act in this life to get a suitable next body.
 

ज्ञेयं यत्तत्प्रवक्ष्यामि यज्ज्ञात्वामृतमश्नुते ।अनादिमत्परं ब्रह्म न सत्तन्नासदुच्यते ॥१३॥
I shall now explain the knowable, knowing which you will taste the eternal. This is beginningless, and it is subordinate to Me. It is called Brahman, the spirit, and it lies beyond the cause and effect of this material world.

A colour blind person's knowledge of colour is no knowledge but ignorance. Similarly, people unable to know themselves different from body, perceive the world as per the perceptions imposed by the limitations of their mind and body. 
So, how does one check whether one is advancing in knowledge or ignorance in the name of knowledge? Lord Krishna explains 20 items which a person finds on the path of real knowledge. 
Which are they?
How many do we possess and to what degree?
INQUISITIVE !!
 

A colour blind person's knowledge of colour is no knowledge but ignorance. Similarly, people unable to know themselves different from body, perceive the world as per the perceptions imposed by the limitations of their mind and body. 
So, how does one check whether one is advancing in knowledge or ignorance in the name of knowledge? Lord Krishna explains 20 items which a person finds on the path of real knowledge. 
Which are they?
How many do we possess and to what degree?
 

The whole world is suffering because people are mistaking ignorance for knowledge. Knowing a snake as rope is not knowledge. Its rather disastrous ignorance. Thus, Arjuna asks two very fundamental questions:
What is knowledge?
What is the end of knowledge?