Generally I would ask if someone was interested in having a deep discussion about their highest principles of importance... (not in those exact words)...
Generally people aren't capable of this at all, because they either don't have a very solid idea of how they relate to those things, in which case you can only offer them suggestions and encouragement about developing regard for such idealistic parameters upon which to create a mental framework of belief.
Lots of people from various walks of life have different state's of belief, each usually with their own strengths and weaknesses.
Atheists who are such because of a single ordered mentality should be the most spiritually advanced non-believer to discuss with, unless they are too fixed on their social status of being one of the scientific-intellegencia that gets its power from being in authority: by wielding a lofty and loose epistemology (scientific reign in the form of authority can only be felt and expressed as blind faith: as the philosophical rigor for science's validity is so feeble it creates a brittle and nervous kind of mental framework that can't cope with any proper reasoned critique of its flaky collection of its 'highest principles of importance').
Agnostic Atheists therefore exert greater strength in their determination because they generally have exerted more intelligence by not falling down into serving the false tower of scientific apologetics, but often when they abandon that false faith, they presume there is no better rigor to be adopted in the absence of scientific-belief, and so they settle on dividing their intelligence into a nebulous collection of interests that may find some eratic level of a cohesion: while coherency is relegated to such an unlikely or impossible subject matter, that they become incapable of making ground in any discussion that goes in ONE DIRECTION:- because they can only discuss anything in terms of the myriad perspectives each of their intellect's parts happen to currently be PRONE to. So because their intelligence is prone to their mind on such a basic level, there is no way to access a discussion with their intelligence to convert the whole intellect that is choosing to relinquish its controling force in favour of subscribing to an aggregated mental reading of whatever the mind is showing the intelligence as feedback (ergo: their intelligence is so slow and lazy from setting its focus on all the things that 'are possible', it risks too much when asked to let those spinning plates collapse down that, if it were to retract itself and develop the "single eye" the mind must possess as its driver to avoid the death from false ego). [note: "the single eye", is actually a biblical quote]
In my experience, most Protestant Christians actually fall into the "agnostic atheist" critique I just laid down, just under the label of "Christianity", which means there are some fixed divisions and distinctions being cast onto all the mental feedback the mind is producing by itself: but its impossible to engage with such a fixed filter, because it isn't based on principle, its based on narrative which is a type of non-thinking that can't be addressed without insulting the intelligence's feeble capitulation to "fairy tale thinking": which most so called Christians use as the bed rock of their mental frameworks (all narrative frameworks are therefore the root of all noxious beliefs, but people don't have the humility that is required to be rational with their intelligence, they give importance to the protection of their fractured investments their intelligence has decided to serve).
In my experience, most consciously identifying Hindu's are in a much better philosophical mood to be converted, because intellectually they are preparing themselves for the work of salvation, although usually the ego will use dogma successfully to shield itself from real progress, which is bound to happen within every form of organised religion.
Its funny, because whenever I talk to an 'agnostic atheist' sort, I first have to try to suggest to them the relevance and necessity of the quest to discover or develop a single mental framework; and when I talk to 'hard line' atheists, I first have to convince them that their mental framework is philosophically incoherent and obviously flawed and in need of displacement- generally 99.99% are too afraid to move from their position without the system-comforts their current self-identity provides them, the integrity of the individual is not appealing when its not mirrored by an index of the world's subculture matrix, leaving me to conclude, all self-identity attachments are a very basic form of organised religion that people aren't capable of overcoming wherever they are at.
In my experience therefore, conversion doesn't happen; but then I wouldn't say I've come across anyone who was a real seeker. I imagine you have to be able to have an open discussion with someone who is stilling looking into the questions of faith, who is trying to understand all the various different systems of belief inside each possible perspective (like someone who is going to a clothing store and doesn't have an idea about what is considered fashionable, and can't decide what is he/she considers comfortable until they have tried on every kind of garment they can manage to experience: of course, if any sort of fashion sense is used early on, the whole project can be tainted and you end up with very limiting options (that perhaps you will only feel the effects of in certain seasons of climate when you see your sensibility for true comfort was distorted...)).
