Let $\mathbb{P}$ a poset. The following are equivalent.
$(1)$ $p\Vdash \varphi$.
$(2)$ $\forall r\leq p(r\Vdash \varphi)$.
$(3)$ $\{r: r\Vdash \varphi\}$ is dense below $p$.
I am confused when trying statements of the form $\Vdash \varphi$ where $p$ does not appear.
What does it mean $\Vdash \varphi$ ?
Can someone explain me please. Thanks
Usually when we write $\Vdash\varphi$ that just means that any $p\in\mathbb{P}$ forces $\varphi$ or equivalently $\{r;r\Vdash\varphi\}$ is dense in $\mathbb{P}$. If $\mathbb{P}$ has a maximum element $\mathbb{1}$ then we can also write $\mathbb{1}\Vdash \varphi$ for $\Vdash\varphi$.