As the word ‘philosophy’ implies (from ‘philo-’ meaning love and ‘-sophy’ meaning ‘true knowledge’), all genuine enquiry is a love affair with Truth. And reason – in particular the higher reason – is just a means through which love works, to express itself in the affair.
But, since reason is only a means of expression, it is subject to love and not the other way around. The workings of love are not subject to reason and cannot rightly be directed or described by reason. The only proper use of reason is to question false beliefs, in search of the One Truth which is loved beyond all else. It’s only through such all-consuming love that every last remaining trace of falsity may be surrendered, on the way to truth.
Just how love works, through this surrendering enquiry, is not a subject to which reason properly applies. When a sadhaka’s love for truth is genuine enough, that love for truth manifests itself in the form of a karana guru, within or without and of sadhanas or investigations which are thereby discovered. A ‘karana guru’ is a teacher (guru) who is at one with ‘karana’ – the inmost source within each sadhaka. Love for such that which teaches, whether internal or external, is the highest devotion.

Love is the feeling or sense of oneness with another. If you correctly understand yourself not to be beyond body, senses and mind, but to embrace them as a living organism at one with all of Nature, your love for another will also be for that same humanity, that oneness with Nature. Because there are not two Natures and two selves, but only One, and love is its nature.
If your understanding is incorrect, and you divorce the humanity in yourself and in the other, replacing it with some pious attitude of Godliness, then your ingenuine love will turn to hatred upon any slight.
Genuine love, on the other hand, absorbs everything into you, the so-called good with the bad, the humanity with the divinity and hence duality dies, transformed into objectless love.

So also bhakti or devotion is a mental attitude directed to an object, generally an ishta-deva [a chosen form of God]. This by itself does not give the ultimate result, moksha. Moksha [liberation] is impersonal. To attain moksha, the goal of bhakti has to be impersonal, not simply for one’s self but for the liberation of the entire dharmic field. By first understanding ourselves and our shared humanity, we come to understand the Nature of God. But the Truth about God is the very Truth about ourselves, obtained in the deepest of all examinations of our beliefs and unnatural tendencies. Therefore, the highest of all love is the love of Enquiry, vicara marga, a love that enables one to persist beyond the nagging desire for the superficialities of life and a true devotion toward that which is Real, that which is the Truth of all Nature.
This is real bhakti, which establishes one in Atma. This is mukti (liberation). This is vastu-tantra, the outcome of Truth. Shri Shankara defines real bhakti of the highest order as follows (in Viveka-cudamani, 31): moksha-sadhana-samagryam bhaktir eva gariyasi
sva-svarupa-’nusandhanam bhaktir ity abhidhiyate
[Among all ways of seeking to be free, it’s love that is the best, one must agree.
To question one’s own truth, to ask what’s there, that is the love of those who ask with care.]

Written at Chinmaya Vibhooti, Kolwan, India