When we positively assert something, we are making ontological claims. We are all doing it all the time, often without even knowing it. We are essentially claiming that a phenomenon or thing 'is' (exists) or that A causes B, for example. We can also make a positive ontological claim of non existence or that A does not cause B. To be intellectually honest, these assertions carry with them an obligation on our part to support that claim using reason and evidence.
We live at an amazing time. Information has never been so available and abundant. Modern technology affords virtually every human being the ability to access a global database of human knowledge and information with only a few keystrokes and a cheap internet connection. We have the instantaneous capability to query, parse and review all of recorded history, legal and political deliberations and records, public companies' financial information, education resources and technical scholarly material, including the most cutting edge ideas and data in science and technology.