<p>Johansson et al. have recently presented a system for theory exploration, that is, coming up with lemmas based on your definitions. You can find their implementation on <a href="https://github.com/moajohansson/IsaHipster" rel="nofollow">GitHub</a> and the paper on <a href="http://arxiv.org/pdf/1405.3426" rel="nofollow">arXiv</a>. In the paper, you will also find a lot of examples. The only drawback is that, as far as I can tell, their implementation only works with Isabelle2013-2.</p>

<p><em>Johansson, Moa, et al. "Hipster: Integrating Theory Exploration in a Proof Assistant." Intelligent Computer Mathematics. Springer International Publishing, 2014. 108-122.</em></p>
how to discover new lemma or guess or search the next lemma which want to be proved in Isabelle
<p>i do not have example, but i googled some people can 
use Isabelle to search lemma and discover new lemma with Isabelle</p>

<p>do not know where give hints to discover or search next lemma after current lemma proved automatically</p>

<p>can you give examples that how to discover lemmas?</p>