Introspection / What it is and what it does
The self-existent Brahman created the mind and senses with outgoing tendencies. The mind has a pernicious habit of externalisation from time immemorial. So you behold the external universe and not the internal Self. It is the Vikshepa-Sakti or Maya (The power of Maya that projects the Universe and causes movement and superimposition) that draws you out. From your childhood, you are taught to look to the external world and not to the internal, psychic world. You have entirely lost the faculty of introspection.
To have a comprehensive understanding of what is going on in the inner 'mental factory', a Suddha Buddhi (pure reason) and subtle intellect with power of introspection is needed. You will have to turn the mind inside, then concentrate all its powers and throw them upon the mind itself, in order that it may know its own nature and analyse itself.
Make a vigorous and earnest search within. Do not trust the mind and the Indriyas (senses). They are your enemies. Woman and wealth are your bitter foes. These are two great evils.
In introspection, the mind itself is the subject of study. A portion of the mind studies the remaining portion of the mind. The higher mind studies the lower mind. Introspection is apperception (Conscious perception with full awareness).
Just as you watch the work done by a coolie, a portion of the mind watches the movements of the rest of the mind. If you are one with the mind, if you identify yourself with the mind, you cannot know your defects. If you are a Sakshi or silent witness of the mind and if you practise introspection, you can know your various defects.
By a careful watch, many defects are detected and removed by suitable Sadhana. Enter a quiet room. Enter into silence daily for about fifteen minutes, morning and evening. Introspect. Watch the mind carefully. The mind will be doing either thinking, planning, feeling, knowing or willing. You will have to find out through subjective introspection what the mind is exactly doing at a particular time. To go through this practice, you must have Antarmukha Vritti (A state in which the mind is turned inwards and is withdrawn from objects), a subjective mind and a subtle Buddhi. Buddhi can be rendered subtle by study of philosophical books, Satsanga, control of Indriyas (Dama) and Sattvic food. The constant utterance of holy Names of God as Hari, OM, Narayana, Rama, Siva purifies the mind-stuff and helps make the mind introspective (Antarmukha).
How To Practise Introspection
You are the best judge of your mind. Introspect by living alone in solitude or retiring into a calm room for an hour. You must sit quiet in a solitary room alone, with closed eyes and watch the activities of the mind. You will then know your defects and weaknesses very clearly.
You should afterwards feel the necessity of removing them. Then your Svabhava should agree to change. You must know the right method to remove the defect. You must apply the method constantly. Then only improvement will set in. Constant application of the Sadhana is an indispensable requisite.
You must watch the improvement every now and then, say, once a week, a fortnight or a month. You will have to keep a record of your progress (spiritual daily diary). You must watch carefully whether you are progressing in the spiritual path, whether you remain stationary or retrograding, whether the mind is distracted or concentrated. If it is distracted, you must remove the distracting causes one by one with patience and vigilance by suitable methods. If one method fails to bring about the desired results, you will have to combine two methods (the Yogic methods and Vichara).
Remember the triplet, viz., self-analysis, self-reliance, self-determination. It will be of immense use in your spiritual Sadhana. Analyse your self through introspection. Find out the nature of your Vrittis (Mind's modifications). Find out what Guna (quality) is predominating at a particular moment, whether it is Sattva, Rajas or Tamas. How long can the mind be absolutely fixed on your Lakshya (point of meditation)-either God, Brahman, idea or object, whether internal or external? How long can the mind be fixed on the object, rose and rose alone to the exclusion of all other objects-whether two seconds or two minutes or five minutes or half an hour? This is self-analysis. Rely on your self alone. You are your own redeemer and saviour. Nobody can give you Moksha (Liberation).
You will have to tread the spiritual path step by step. Books and Gurus can show the path and guide you. This is self-reliance. Make a strong self-determination, "I will realise God. I will have Atma-Sakshatkara (Realisation of Atman, direct experience of the absolute Being) or Brahmanubhava (Self-realisation; God-realisation; Absolute experience) this very moment and not in the uncertain future." This is self-determination.
Wordlings have no time to think over even for a few minutes the life-problems, the mystery of life, etc. They get up in the morning. Their minds usually run to the special objects of enjoyment on account of Raga (Attachment, desire). Their mental energies are poured forth in the usual grooves and avenues-in thoughts of body, thoughts of eating and dressing, thoughts of wife, children, friends and also thoughts of office-work and business; and thus, the day is over. The same routine follows day after day, week after week. Years roll on and life is wasted. It is highly lamentable, indeed!
Only he who does Manana (reflection) and introspection through Antarmukha Vritti can change his worldly nature. In him only the idea of Brahman can get permanently lodged.