# What does $\bigwedge$ mean in lambda calculus?

In the Wikipedia article on Fixed-point combinator in the Values and domains section, we find the following:

$$x^2 = -1 \implies x = \frac{-1}x \implies fx = \frac{-1}x \bigwedge Yf = x$$

What does the $$\bigwedge$$ mean? How does $$x = \frac{-1}x$$ imply $$fx = \frac{-1}x \bigwedge Yf = x$$? My best guess is observing that $$\lambda be.eb = \overline{b^e}$$, then guessing that $$\bigwedge$$ means exponentiation, but that would still not explain why $$fx = x$$ or $$\frac{-1}x \bigwedge Yf = x$$.

• This is most probably '$\land$', the logical 'and' connective. Dec 10, 2021 at 15:47
• Thanks. I'm still confused by $\frac{-1}x \wedge Yf$ in this context. Dec 10, 2021 at 16:27
• Yes, it is conjunction (logical and): $\land$. It reads: $fx=\frac {−1}{x} \text { and } \text {Y}f=x$ Dec 10, 2021 at 16:36

Examining the source code of the Wikipedia page indicates that this symbol is generated by \land, which denotes "logical and", or conjunction. Note the difference in size and weight between $$\bigwedge$$ and $$\land$$.