If you suppose you are a person without a spiritual bone in your body you are wrong - you are merely unaware of what is happening in your thinking; and perhaps (as a theoretical act) prone to deny its validity.
You may suppose that you live merely by 'evidence', by the evidence of what is actually-there; but a few moments of reflection should remind you that perceptions-as-such have no meaning.
If spiritual is understood to refer to anything which comes from outwith the five-sense perceptions (whether or not amplified with scientific machinery) then you are spiritual, because the meaning of all perception comes from somewhere that is not perceived.
Ideas, concepts, all kinds of understanding... these are not perceived - so, where do they come from? Maybe you suppose they are 'subjective', they comes from the minds of people? Yes, but... it all depends on what you mean by subjective...
Real-reality, in actual practice, is always and everywhere and by everybody made-sense-of with - or by means of - the human mind.
So, we are not cut-off from the world outside, we are not cut-off from other people - we are not cut off from anything that we think about because we are involved-in making sense of everything that is made sense of.
And that also means that whenever there is agreement between people as to what is real - this is due to agreement in their minds. We share all ways of making sense of the world - indeed we could not even discuss the matter, we could not even disagree about interpretations! - unless we shared a basic understanding: shared a basic way of making-sense of our perceptions.
This is where things start getting interesting... because if there is any real-reality, then it means that the concepts, ideas, understandings must be objective - or else there would be as many realities as there are people, and each person's reality would change with age, mood, illnesses, and a thousand other factors.
So this analysis brings us beyond evidence and to metaphysics - to the point of basic assumptions which we must make on the basis of intuition, inner convictions - whatever you want to call it. Because we are, I think, forced to decide whether this is a world in which real, genuine, understanding is possible - or whether it is not.
If you, personally, assume that understanding is possible, then you are a spiritual person - whether you know it or not, whether you admit it or not.
(And if not - then why are you reading this?)
Note: The above argument is adapted from Rudolf Steiner's early philosophical works, especially The Philosophy of Freedom (aka The philosophy of Spiritual Activity/ Intuitive Thinking as a Spiritual Path).