The existence of empirically calculatable things is, to someone without a Philosophical mind, a certainty. I am typing on a computer, a mouse in my hand, thus both must be true. From this reasoning, it follows that my hands and fingers are also physically true. This, however, is where Philosophers like to diverge from the normal instances of what is reality? I was asked to contemplate the nature of a banana – in argument that it is not what everybody says it is.
To a realist, a banana is a banana, that is, an object of nourishment, a real, objective quality ‘out’ in the world. Saying it is a banana is not creating a banana from the language; it is an affirmation of what we already know. On the other hand, an anti-realist believes that what a banana is changes within the relative community. Thus it depends to whom you talk.
If we were to take that what a banana is depends on not its physical state, but what it is for the individual, a banana would change. For instance, you might consider a banana by its nutritious content, but that could be anything in its field. What sets a banana apart from an apple? Its colour? Its flavour? To someone with no clarity of taste or sight, they are both fruits.
It is generally established that a banana is a food-stuff, but if we were to present an alien with a banana, its first thought might not be to eat it, due to the fact that substances similar to the banana might not be eaten on the alien’s home planet! And would the alien know that what it held was a ‘banana’? I say not.
The idea of a banana is completely different to the existence of a banana. One might attest that one could have an idea of some multicolour banana in one’s head, but that does not allow it to necessarily exist. The idea may lead to the physical creation – via experiments – but, again, this is not verification that it exists purely through will-power. Gaunilo refuted St. Anselm’s ontological argument of God[i] by proclaiming that anything could be substituted into the sentence without becoming a greater power. For instance, anyone can think up an island that is greater than any other physical island, but that it would be subjected to change – and one could imagine another island better than the first. (St. Anselm’s reply was to point out that ‘island’ is contingent, God is not.) Either way, there are flaws that thinking of something does not prove its existence. I can think of unicorns, do they then exist?
Another question that arises is: how do we know what we see as a banana is actually a banana? The evidence may be there – it looks, smells, even tastes like a banana – but can we be sure that what we hold in our hands is really a banana and not an imitation or a creation of our own mind. To argue against the existence of a banana, one could bring up the question of whether we really experience the objects that surround us; perhaps the image of a banana is simply imprinted into our minds from some time when bananas really ‘existed’, but now have been transformed (though I shall not delve into the idea of plots to deceive us of our senses). If the ‘reality’ that we live in is created from the mind, a banana would be another piece of information in our mind, and thus would not be what everyone knows as a banana. Not really.
[i] “That than which no greater can be conceived.”