In vino veritas

This I certainly know what it means. In wine you see the truth. Oh yes, you do. Thing is, that when you're slightly under the influence, you express things that you do not dare when sober. These things may be over-the-top, and expressed in a way that is slightly unappropriate, but has nevertheless a core of truth to it.

In my home country we have a saying (translated): "From children and drunks you hear the truth".

So, in vino veritas :)