Tad uparagapeksitvat cittasya vastu jnatajnatam.
Tad-uparage = the colouring thereby; apeksitvat = because of needing; cittasaya = of the mind; vastu = an object; jnata = known; ajnatam = unknown.
In consequence of the mind being coloured or not coloured by it, an object is known or unknown. (IV 17)
Our knowledge of the objects of the world is directly proportionate to the effect they have on our mind. Some objects, persons, incidents affect us very deeply. We are totally 'coloured' by some emotions. Great devotees like Mirabai exclaim, "I am totally coloured with His colour". Our minds are modified more or less (though modification is not as good a term as 'colouring') depending upon our interest and attachment to the things. Complicated scienctific concepts may not 'colour' the mind of a novices so deeply. His understanding would be very superficial. Same is true for philosophical ideas. As and when our interest and need in philosophy deepens, by repeated contemplation, the ideas get crystallized, colouring our mind more and more.