Yoga sutra 1.42
Tatra śabdārtha-jñāna-vikalpaiḥ saṁkīrṇā savitarkā samāpattiḥ
Complete union with gross objects occurs when world, meaning and knowledge are mixed together
All the various meditations so far, Patanjali calls Savitarka, that is meditations with ‘reasoning’. Later on, Patanjali gives us higher and higher meditations to attain Samadhi.
In these Savitarka, you tend to keep the duality of subject and object, which results from the mixture of word, meaning, and knowledge. For example, there is first the external vibration, the word; this is carried inward by your sense currents and is the meaning. Then follows your perception of the same which is a reactionary wave, and when world, meaning and knowledge are mixed together there results actual knowledge.
Damian Cadman-Jones is an authorised teacher of Prana Vashya Yoga™