Hi Ursula,

I think you mean the so-called end of the proof sign, or QED (Quod Erat Demonstrandum). You can use this:

\definesymbol[QED][\mathematics{\square}]
\def\qed{\wordright{\symbol[QED]}}
\starttext
This is the end of our proof. \qed
\stoptext

In principle it is included in ConTeXt, but it seems that in the latest version I have (2024.01.23), the command \qed is broken.

Best regards: Otared

On 8 Feb 2024, at 12:23, Ursula Hermann <ursula.hermann@univie.ac.at> wrote:

Dear List, 

I am at Home  and have the following example.:

\starttext
\margintext {1.1.1}
{\bf Beispiel 3.2.17 (Vertauschung von All- und Existenzquantor).}
\par
{\it Sei M die Menge aller Männer und F die Menge aller Frauen. Die
Aus-\par
sage h(m, f) sei ”m ist verliebt in f“. Unter diesen Voraussetzungen
machen Sie sich die Bedeutung der beiden Aussagen klar.\startalignment[right]\square\stopalignment}\stoptext}

There should be a sign like this □ at the end of the proof. 

Uschi
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