Readers of this volume are invited on a journey through alogician's life, as witnessed by his colleagues and friends.They will have the opportunity to immerse themselves in theregions of set theory, arithmetic, data analysis, algebra,fuzzy logic and other topics that Petr Hájek has shared withthe contributors. Each of the contributions is unique in itsapproach as well as its personal envoi, helping to create afull-blooded, vivid and genuine picture of the man who hasbeen so emphatically influential to so many of us. Matureand fresh ideas blend in the texts which will, hopefully, makean interesting and enjoyable reading for Petr Hájek as well asfor any keen logician.