Recently I've been interested in creating somewhat non-constructive solutions to problems using the concept of a transcendence basis of $\mathbb{R}$ over $\mathbb{Q}$, which exists assuming the Axiom of Choice but I only know some basic Field Theory. As part of my increasing understanding, I ask:
Let $W$ be the transcendence basis for $\mathbb{R}$ over $\mathbb{Q}$. Is it true that $$\mathbb{R} = \bigcup_{w\subset W, \;w \text{ finite}}\mathbb{Q}(w)$$? What if we replace "finite" with "countable"?
Perhaps I am missing something, but, quoting for instance from this MSE post:
So an element like $\sqrt{2}$ will not be in any of your $\mathbb{Q}(w)$.