Why make so much of fragmentary blue
In here and there a bird, or butterfly,
Or flower, or wearing-stone, or open eye,
When heaven presents in sheets the solid hue?Since earth is earth, perhaps, not heaven (as yet)--
Though some savants make earth include the sky;
And blue so far above us comes so high,
It only gives our wish for blue a whet.
— Robert Frost
Why would anyone ever believe in Platonism, the view that there are transcendent 'forms' that exist over and above spatiotemporal reality, that are somehow supposed to explain it? This essay is an attempt to answer that question.
One natural view about
truth is to think that for some claim to be true, there must be something in
the world that makes it true. For example, it seems true that ‘Rowan likes
coffee’ because I do, in fact, like coffee. ‘Grass is green’ is true because
grass is, in fact, green. Of course, the case of colour (like everything else)
becomes complicated: what exactly do we mean by ‘green’ and what is it for
something, like grass, to be green?
Of those that attempt to explain this seeming fact, different stories could be told. But however this is done, there will be some reality that makes the fact true. For example, one view might say that ‘green’ refers to the surface properties of physical bodies that reflect light within a certain range of wavelengths. This view says that ‘grass is green’ is true because the properties of grass mean light is reflected in just this way. Another view says that green is a specific qualitative character of experience, one that is not part of the physical world. Such a view can nonetheless say that our statement ‘grass is green’ is still true because we perceive grass and in perceiving it, our experience is of this specific character. Finally, another view thinks that grass is green because grass has the power to produce green sensations in us. This power that grass has to make us have a certain kind of sensation is what makes ‘grass is green’ is true. In each case, once we settle the interpretation of ‘green’ we find that there is some reality it refers to that makes claims like ‘grass is green’ true. This general view of truth is called the ‘truthmaker’ view, which basically says that every truth has a truthmaker. I think the view is basically right. And even if it is not exactly right, I think it at least constitutes the right kind of attitude we should take towards doing metaphysics – an attitude that thinks truth does not come reality-free.