'The meaning of life' - always assuming that by 'meaning' we mean 'explanation' rather than 'purpose' (which wrongly presupposes the necessity of purpose) or 'secret of happiness' (which is a question that belongs, if anywhere, in psychology) - is not a great philosophical mystery but a question that has been concluded for at least a hundred and fifty years.
It was answered by Darwin, much like that other great supposed imponderable, which came first, the chicken or the egg? (Since a chicken evolved from some earlier species of bird, the answer is the egg.)
The meaning of life is genetic propagation.
As meaning is no great mystery, neither is life itself.
The difference between living and non-living things is a slippery one, with little practical meaning. There is no actual scientific sense in which we and trees and elephants are ‘alive’ and the earliest replicators, or rocks, or water, are inanimate, mechanical, ‘dead’. This is vitalism – a totally outmoded concept. It does not so much define life as opine ‘I know it when I see it’.
But there is a deeper philosophical point here about our propensity to ask these questions in the first place.
A rock does not ponder the meaning of life because, we must assume, it cannot. But if it could, would it feel the need to? The answer is of course yes, because anything capable of formulating such an enquiry is therefore justified in doing so.
But a rock that could think is obviously a rock no longer. So there is a circular paradox here.
We assume the question is relevant for us, because we are able to ask it - but which is the chicken and which the egg: the validity of the enquiry or the ability to formulate it?
What we can see, very clearly, is that it is not much of a question as far as the rock is concerned.
On the rock's behalf, as it were, we can see that the meaning of life is not something it has any especial business being troubled by.
This should make us feel just a little bit uneasy.
If ultimate meaning is demanded by us because our greater complexity than the rock seems to justify the enquiry, then it suggests that we ask the question because we can, and then feel ourselves more entitled to do so than something that can't, purely because we have instinctively and arbitrarily selected 'ability to ask the question in the first place' as the defining differential.
But elephants cannot formulate it either, and yet are surely entitled to enquire if only they could? Why not the rock, then?
If we accept a mechanistic model for brain complexity we have no more or less innate need to ask the question than a rock does.
We are 'alive' and rocks are not?
Even if you cling to vitalist principles, surely the difference is not absolute but one of degrees, travelling in gradiating progression from rocks, through sponges, then trees, amaeoba, insects, elephants and us, with a million more intermediates each step of the way. Where on that ladder does life begin - and, more pertinently, end?
Life is a red herring. What is really concerning us here is existence, a state common to humans and rocks. 'Life' and existence are two very different things, and it may be sheer self-prioritisation to assume that sentience is by definition more important than mere presence - and thus demanding of a different answer.