Regarding synaptic, or rpm, zypper, yast, (other linux installers)., going down that path would require TheBrain Inc to deploy significant personnel-resources to the task, as a different release of thebrain would need to be made available for each of the many distribution types. Of course, this would result in a smoother end-user experience, but would the effort be worth it? As TheBrain is a java-based application it does not have complicated installation requirements. I`m guessing that your Linux distribution does not prevent alternatives to synaptic from installing software. Rather, the distribution can not be expected to provide installation support for software that is not included in the distribution. For that reason, instructions on how to do so are probably lacking.
However, here on this board, there are many of us who have successfully installed and now use TheBrain. Please tell us the name of your distribution, and we`ll see if we can help you get up and running.
The basic steps are
1) open a terminal where thebrain has been downloaded to.
2) type sh TheBrain_unix_7_0_4_1.sh
3) press enter.
4) if the distribution complains about using the default installation folder, just create and use a folder in your own home directory.
Synaptic is a graphical package management program for apt. It provides the same features as the apt-get command line utility with a GUI front-end based on Gtk+.
APT simplifies the process of managing software on Unix-like computer systems by automating the retrieval, configuration and installation of software packages, either from binary files or by compiling source code.``