Gnosticism - Irenaeus and his Against Heresies - Catholic Orthodoxy vs the Valentinian Gnostics

Gnosticism came upon powerful and sustained assault beginning in the 2nd century, most famously by Irenaeus and in Five Book "On the Detection and Overthrow of the Falsely-Called Gnosis" better known as simply "Against Heresies." In fact, prior to the discovery of the Nag Hammadi Library in 1945, Irenaeus was our only real insight into these ancient gnostic spiritualities. With Irenaeus becoming a "Doctor of the Church" just this year (2022) and Gnosticism a more popular religious movement than ever let's explore this most ancient polemic against Gnosticism. Does Valentinus represent Gnosticism fairly? What are his exact religious and philosophical critiques? What can we learn about ancient Gnosticism and the proto-orthodoxy from his attack? How did this work earn him the title of "Doctor of the Church"?
https://youtu.be/9wi5SixWICY