Question
Bhagavad Geeta 5.4 - Can one attain samādhi by practicing science?
Answer
The problem is with translation of the word Samkhya it is used as a synonym of Jnana Yoga(The path of Liberation through Knowledge).
Adi Shankaracharya, Bhagwad Ramanujacharya and different Other Acharyas have enlightened us on this through their commentaries.
Adi Shankaracharya's Comments:
This defect does not arise. Although the question was put by Arjuna merely with regard to renunciation and Karma-yoga, yet the Lord, without actually avoiding them, and by adding something special which was intended by Him, gave the answer by expressing them through other words, ‘Sankhya’ and ‘(Karma-) yoga’. Those very ‘renunciation and ‘Karma-yoga’, when they are (respectively) associated with Knowledge and such of Its means as equanimity etc., are meant by the words ‘Sankhya’ and ‘yoga’. This is the Lord’s veiw. Therefore there is no discussion out of the context.
Samkhya is not for what we today study as science, but it is JnanYoga path or path of Knowledge, it does not involve science as scriptures directly give that knowledge. The Science Just cannot find the root of the Material world because Bramhan is all pervading and doesn't need anything to prove his existence.
Jnana means Knowledge of Self and Bramhan or Atmajnana and Bramhajnana, Since science till the day is unable to understand nature and existence of Atman and Bramhan. I don't think modern day Science can be helpful in attaining Samadhi.
From Bhagwad Ramanujacharya's Commentary
Those who say that Karma Yoga and Jnana Yoga are distinct because of the difference in results, are children, i.e., are persons with incomplete knowledge; they do not know the entire truth. The meaning is that they do not possess true knowledge, who say that Karma Yoga results in Jnana Yoga only and that Jnana Yoga alone results in the vision of the self and that the two are thus distinct because of the difference in their fruits. But on the contrary as both have only the vision of the self as the fruit, a person who is firmly set in one of them, wins that one fruit common to both.
On a side note AtmaJnana is not just realizing that you are atman the true self but to apply it in real life,i.e by doing nishkama karma and giving all fruits of actions to Krishna (Krishnarpanamastu) or as Seva or Kainkarya to Krishna.
As you act as an atman and see others as Jeevatman rather than bodies you will slowly realize that the worldly perspective of Bodies and materials is not the ultimate true nature. Rather only Jeevatman and Bramhan exist and goal of jeevatman is to attain Bramhan or Shriman Narayana (This is Vishitadvaita Perspective of Bhagwad Ramanujacharya).
In Advaita Perspective (propounded by Adi Shankaracharya) if you realize that you are Atman or Nirguna Brahman is your true nature, then there is nothing more left to realize and you can attain Kaivalya.
There is a relevant verse in Shrimad Bhagwatam with this chapter of BG i.e Karma Vairagya Yoga.
Even while engaging his senses in contact with their objects, one who sees this whole world as the energy of Lord Viṣhṇu is neither repelled nor elated. He is indeed the greatest among devotees. SB 11.2.48
You can read the commentaries here and/or here, Vaishnava commentaries only
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