The term wisdom is used for the tech tree in Xhodon. You just have to click on the link in the menu bar in the upper right corner. There you find precise descriptions about all buildings, creatures and sentinels.
At the left side of the table you can click on links for more information. At the right are all the prerequisite for conjuring buildings or summoning creatures. If a prerequisite is red coloured you haven't fulfilled it yet. Prerequisites colored green are already met.