  We explore the possibilities of enforcing and preventing consensus in
continuous opinion dynamics that result from modifications in the communication
rules. We refer to the model of Weisbuch and Deffuant, where $n$ agents adjust
their continuous opinions as a result of random pairwise encounters whenever
their opinions differ not more than a given bound of confidence $\eps$. A high
$\eps$ leads to consensus, while a lower $\eps$ leads to a fragmentation into
several opinion clusters. We drop the random encounter assumption and ask: How
small may $\eps$ be such that consensus is still possible with a certain
communication plan for the entire group? Mathematical analysis shows that
$\eps$ may be significantly smaller than in the random pairwise case. On the
other hand we ask: How large may $\eps$ be such that preventing consensus is
still possible? In answering this question we prove Fortunato's simulation
result that consensus cannot be prevented for $\eps>0.5$ for large groups. %
Next we consider opinion dynamics under different individual strategies and
examine their power to increase the chances of consensus. One result is that
balancing agents increase chances of consensus, especially if the agents are
cautious in adapting their opinions. However, curious agents increase chances
of consensus only if those agents are not cautious in adapting their opinions.
