I sure hope so, or else my very existence is questioned... Although perhaps it'd be a nice change to exist in some observational realm.
I have to say, I am most definitely an INFP and apparently 5w6. Odd, sure, but it makes a lot of sense to me. I am perhaps the only INFP studying a hard science of whom I know (Chemistry degree, theoretical/physical), but it makes a lot of sense to me. As an INFP, I am a true idealist, a dreamer, and I like to dream up possibilities deemed entirely illogical and irrational by most other types. I also notice finer details and I personify everything in life. So with Science which you might agree is definitely predominated by head types suits me as a 5w6 INFP because I have the capacity to think logically enough to understand and contribute to hard facts and discussions, but also the ambition enough to challenge common perceptions and revolutionise "impossible possibilities". It is also interesting to note my way of thinking about such subjects. When thinking of molecules/simulations/equations/fact, I think emotionally, with my head. If that makes any sense. I am applying logic to feeling and vice versa. So I can think logically about a system, but I can dream about its shape and think of it like a dance, often talking about atoms as sentient beings and wondering what it would be like to be a Ca atom etc and all of such whacky craic.
I also notice in my life that when thinking abstractly and when thinking about my own thoughts and feelings, I am whole-heartedly a completely irrational INFP to the core, and feeling heavily predominates my thoughts. But I also have an acute ability to focus in and analyse situations to which I do not feel heavily involved, so while I can recognise and empathise with how other people are feeling without them even knowing, I can also understand why they do/say what they do/say and can apply logic and reason to whatever obstacles might come up.
It's an odd type, INFP 5w6, but it works. Just a bit of an outcast and a walking paradox, but there's nothing misconceived or hypocritical about it. I think the hardest part about it is the conflict within, regarding what to do next: do I engage in my altruistic side full of autonomy and teach English as a foreign language abroad in China for the culturally rich experience and the sheer wonder of it all, or do I continue with study/presentations/long hours of analysis with computer simulations and acute degrees of measurement in the lab. Etc. It's a constant battle, but I think being a head type INFP allows you to really understand and engage with what you're thinking about what you're feeling and what you're feeling about what you're thinking and it's all very airy fairy philosophical, but with a point. I understand it and I get it, but it's very difficult to explain.
We definitely exist though. Just kind of somewhere between reality and somewhere else, but it's all interconnected.